diff --git a/toolchain/check/check.cpp b/toolchain/check/check.cpp
index 51392d65458c..47ff599b0790 100644
--- a/toolchain/check/check.cpp
+++ b/toolchain/check/check.cpp
@@ -8,6 +8,7 @@
 #include "toolchain/base/pretty_stack_trace_function.h"
 #include "toolchain/base/value_store.h"
 #include "toolchain/check/context.h"
+#include "toolchain/parse/tree.h"
 #include "toolchain/parse/tree_node_location_translator.h"
 #include "toolchain/sem_ir/file.h"
 
@@ -100,42 +101,48 @@ static auto CheckParseTree(const SemIR::File& builtin_ir, UnitInfo& unit_info,
 // The package and library names, used as map keys.
 using ImportKey = std::pair<llvm::StringRef, llvm::StringRef>;
 
-// Returns a key form of the package object.
-static auto GetImportKey(UnitInfo& unit_info,
-                         Parse::Tree::PackagingNames package) -> ImportKey {
+// Returns a key form of the package object. file_package_id is only used for
+// imports, not the main package directive; as a consequence, it will be invalid
+// for the main package directive.
+static auto GetImportKey(UnitInfo& unit_info, IdentifierId file_package_id,
+                         Parse::Tree::PackagingNames names) -> ImportKey {
   auto* stores = unit_info.unit->value_stores;
-  return {package.package_id.is_valid()
-              ? stores->identifiers().Get(package.package_id)
-              : "",
-          package.library_id.is_valid()
-              ? stores->string_literals().Get(package.library_id)
-              : ""};
+  llvm::StringRef package_name =
+      names.package_id.is_valid()  ? stores->identifiers().Get(names.package_id)
+      : file_package_id.is_valid() ? stores->identifiers().Get(file_package_id)
+                                   : "";
+  llvm::StringRef library_name =
+      names.library_id.is_valid()
+          ? stores->string_literals().Get(names.library_id)
+          : "";
+  return {package_name, library_name};
 }
 
 static constexpr llvm::StringLiteral ExplicitMainName = "Main";
 
 // Marks an import as required on both the source and target file.
-// TODO: When importing without a package name is supported, check that it's
-// used correctly.
+//
+// The ID comparisons between the import and unit are okay because they both
+// come from the same file.
 static auto TrackImport(
     llvm::DenseMap<ImportKey, UnitInfo*>& api_map,
     llvm::DenseMap<ImportKey, Parse::Node>* explicit_import_map,
     UnitInfo& unit_info, Parse::Tree::PackagingNames import) -> void {
-  auto import_key = GetImportKey(unit_info, import);
+  const auto& packaging = unit_info.unit->parse_tree->packaging_directive();
 
-  // Specialize the error for imports from `Main`.
-  if (import_key.first == ExplicitMainName) {
-    // Implicit imports will have already warned.
-    if (explicit_import_map) {
-      CARBON_DIAGNOSTIC(ImportMainPackage, Error,
-                        "Cannot import `Main` from other packages.");
-      unit_info.emitter.Emit(import.node, ImportMainPackage);
-    }
-    return;
-  }
+  IdentifierId file_package_id =
+      packaging ? packaging->names.package_id : IdentifierId::Invalid;
+  auto import_key = GetImportKey(unit_info, file_package_id, import);
 
+  // True if the import has `Main` as the package name, even if it comes from
+  // the file's packaging (diagnostics may differentiate).
+  bool is_explicit_main = import_key.first == ExplicitMainName;
+
+  // Explicit imports need more validation than implicit ones. We try to do
+  // these in an order of imports that should be removed, followed by imports
+  // that might be valid with syntax fixes.
   if (explicit_import_map) {
-    // Check for redundant imports.
+    // Diagnose redundant imports.
     if (auto [insert_it, success] =
             explicit_import_map->insert({import_key, import.node});
         !success) {
@@ -148,21 +155,74 @@ static auto TrackImport(
       return;
     }
 
-    // Check for explicit imports of the same library. The ID comparison is okay
-    // in this case because both come from the same file.
-    auto packaging = unit_info.unit->parse_tree->packaging_directive();
-    if (packaging && import.package_id == packaging->names.package_id &&
-        import.library_id == packaging->names.library_id) {
+    // True if the file's package is implicitly `Main` (by omitting an explicit
+    // package name).
+    bool is_file_implicit_main =
+        !packaging || !packaging->names.package_id.is_valid();
+    // True if the import is using implicit "current package" syntax (by
+    // omitting an explicit package name).
+    bool is_import_implicit_current_package = !import.package_id.is_valid();
+    // True if the import is using `default` library syntax.
+    bool is_import_default_library = !import.library_id.is_valid();
+    // True if the import and file point at the same package, even by
+    // incorrectly specifying the current package name to `import`.
+    bool is_same_package = is_import_implicit_current_package ||
+                           import.package_id == file_package_id;
+    // True if the import points at the same library as the file's library.
+    bool is_same_library =
+        is_same_package &&
+        (packaging ? import.library_id == packaging->names.library_id
+                   : is_import_default_library);
+
+    // Diagnose explicit imports of the same library, whether from `api` or
+    // `impl`.
+    if (is_same_library) {
       CARBON_DIAGNOSTIC(ExplicitImportApi, Error,
                         "Explicit import of `api` from `impl` file is "
                         "redundant with implicit import.");
       CARBON_DIAGNOSTIC(ImportSelf, Error, "File cannot import itself.");
-      unit_info.emitter.Emit(
-          import.node, packaging->api_or_impl == Parse::Tree::ApiOrImpl::Impl
-                           ? ExplicitImportApi
-                           : ImportSelf);
+      bool is_impl =
+          !packaging || packaging->api_or_impl == Parse::Tree::ApiOrImpl::Impl;
+      unit_info.emitter.Emit(import.node,
+                             is_impl ? ExplicitImportApi : ImportSelf);
       return;
     }
+
+    // Diagnose explicit imports of `Main//default`. There is no `api` for it.
+    // This lets other diagnostics handle explicit `Main` package naming.
+    if (is_file_implicit_main && is_import_implicit_current_package &&
+        is_import_default_library) {
+      CARBON_DIAGNOSTIC(ImportMainDefaultLibrary, Error,
+                        "Cannot import `Main//default`.");
+      unit_info.emitter.Emit(import.node, ImportMainDefaultLibrary);
+
+      return;
+    }
+
+    if (!is_import_implicit_current_package) {
+      // Diagnose explicit imports of the same package that use the package
+      // name.
+      if (is_same_package || (is_file_implicit_main && is_explicit_main)) {
+        CARBON_DIAGNOSTIC(
+            ImportCurrentPackageByName, Error,
+            "Imports from the current package must omit the package name.");
+        unit_info.emitter.Emit(import.node, ImportCurrentPackageByName);
+        return;
+      }
+
+      // Diagnose explicit imports from `Main`.
+      if (is_explicit_main) {
+        CARBON_DIAGNOSTIC(ImportMainPackage, Error,
+                          "Cannot import `Main` from other packages.");
+        unit_info.emitter.Emit(import.node, ImportMainPackage);
+        return;
+      }
+    }
+  } else if (is_explicit_main) {
+    // An implicit import with an explicit `Main` occurs when a `package` rule
+    // has bad syntax, which will have been diagnosed when building the API map.
+    // As a consequence, we return silently.
+    return;
   }
 
   if (auto api = api_map.find(import_key); api != api_map.end()) {
@@ -194,15 +254,18 @@ auto CheckParseTrees(const SemIR::File& builtin_ir,
   // Create a map of APIs which might be imported.
   llvm::DenseMap<ImportKey, UnitInfo*> api_map;
   for (auto& unit_info : unit_infos) {
+    // TODO: It may be good to validate filenames here, but that would have use
+    // put .impl.carbon on almost all tests (which are in `Main//default`). We
+    // should probably get leads direction on filenames before enforcing.
     const auto& packaging = unit_info.unit->parse_tree->packaging_directive();
     if (packaging) {
-      auto import_key = GetImportKey(unit_info, packaging->names);
-      // Catch explicit `Main` errors before they become marked as possible
+      auto import_key =
+          GetImportKey(unit_info, IdentifierId::Invalid, packaging->names);
+      // Diagnose explicit `Main` uses before they become marked as possible
       // APIs.
       if (import_key.first == ExplicitMainName) {
-        CARBON_DIAGNOSTIC(
-            ExplicitMainPackage, Error,
-            "Default `Main` library must omit `package` directive.");
+        CARBON_DIAGNOSTIC(ExplicitMainPackage, Error,
+                          "`Main//default` must omit `package` directive.");
         CARBON_DIAGNOSTIC(
             ExplicitMainLibrary, Error,
             "Use `library` directive in `Main` package libraries.");
@@ -230,10 +293,12 @@ auto CheckParseTrees(const SemIR::File& builtin_ir,
   llvm::SmallVector<UnitInfo*> ready_to_check;
   ready_to_check.reserve(units.size());
   for (auto& unit_info : unit_infos) {
-    const auto& packaging = unit_info.unit->parse_tree->packaging_directive();
-    if (packaging && packaging->api_or_impl == Parse::Tree::ApiOrImpl::Impl) {
-      // An `impl` has an implicit import of its `api`.
-      TrackImport(api_map, nullptr, unit_info, packaging->names);
+    if (const auto& packaging =
+            unit_info.unit->parse_tree->packaging_directive()) {
+      if (packaging->api_or_impl == Parse::Tree::ApiOrImpl::Impl) {
+        // An `impl` has an implicit import of its `api`.
+        TrackImport(api_map, nullptr, unit_info, packaging->names);
+      }
     }
 
     llvm::DenseMap<ImportKey, Parse::Node> explicit_import_map;
diff --git a/toolchain/check/handle_import_and_package.cpp b/toolchain/check/handle_import_and_package.cpp
index ded009468445..40a7ef01281d 100644
--- a/toolchain/check/handle_import_and_package.cpp
+++ b/toolchain/check/handle_import_and_package.cpp
@@ -14,14 +14,48 @@ auto HandleImportIntroducer(Context& /*context*/, Parse::Node /*parse_node*/)
   return true;
 }
 
+auto HandleImportDirective(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandleLibraryIntroducer(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandleLibraryDirective(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
 auto HandlePackageIntroducer(Context& /*context*/, Parse::Node /*parse_node*/)
     -> bool {
   return true;
 }
 
-auto HandleLibrary(Context& context, Parse::Node /*parse_node*/) -> bool {
-  // Pop and discard the library name from the node stack.
-  context.node_stack().Pop<Parse::NodeKind::Literal>();
+auto HandlePackageDirective(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandleLibrarySpecifier(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandlePackageName(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandleLibraryName(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
+  return true;
+}
+
+auto HandleDefaultLibrary(Context& /*context*/, Parse::Node /*parse_node*/)
+    -> bool {
   return true;
 }
 
@@ -35,18 +69,4 @@ auto HandlePackageImpl(Context& /*context*/, Parse::Node /*parse_node*/)
   return true;
 }
 
-auto HandleImportDirective(Context& context, Parse::Node /*parse_node*/)
-    -> bool {
-  // Pop and discard the identifier from the node stack.
-  context.node_stack().Pop<Parse::NodeKind::Name>();
-  return true;
-}
-
-auto HandlePackageDirective(Context& context, Parse::Node /*parse_node*/)
-    -> bool {
-  // Pop and discard the identifier from the node stack.
-  context.node_stack().Pop<Parse::NodeKind::Name>();
-  return true;
-}
-
 }  // namespace Carbon::Check
diff --git a/toolchain/check/testdata/packages/explicit_imports.carbon b/toolchain/check/testdata/packages/explicit_imports.carbon
index b1077e470e80..fcd5b188b6bb 100644
--- a/toolchain/check/testdata/packages/explicit_imports.carbon
+++ b/toolchain/check/testdata/packages/explicit_imports.carbon
@@ -12,24 +12,37 @@ package Api api;
 
 package Api library "lib" api;
 
-// --- import_api.carbon
+// --- same_package.carbon
+
+package Api library "other" api;
+
+import library default;
+import library "lib";
+
+// --- different_package.carbon
+
+package ApiOther api;
 
 import Api;
 import Api library "lib";
 
+// --- main_lib_api.carbon
+
+library "lib" api;
+
+// --- main_import.carbon
+
+import library "lib";
+
 // CHECK:STDOUT: file "api.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "api_lib.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
+// CHECK:STDOUT: file "same_package.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file "import_api.carbon" {
-// CHECK:STDOUT:   %.loc3: String = string_literal "lib"
+// CHECK:STDOUT: file "different_package.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_lib_api.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_import.carbon" {
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/fail_api_not_found.carbon b/toolchain/check/testdata/packages/fail_api_not_found.carbon
index 72b0dba05926..11c9d66841de 100644
--- a/toolchain/check/testdata/packages/fail_api_not_found.carbon
+++ b/toolchain/check/testdata/packages/fail_api_not_found.carbon
@@ -18,12 +18,16 @@ package Foo impl;
 // CHECK:STDERR: ^
 package Foo library "Bar" impl;
 
+// --- no_api_main_lib.carbon
+
+// CHECK:STDERR: no_api_main_lib.carbon:[[@LINE+3]]:1: ERROR: Corresponding API not found.
+// CHECK:STDERR: library "Bar" impl;
+// CHECK:STDERR: ^
+library "Bar" impl;
+
 // CHECK:STDOUT: file "no_api.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "no_api_lib.carbon" {
-// CHECK:STDOUT:   %.loc5: String = string_literal "Bar"
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "no_api_main_lib.carbon" {
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/fail_import_default.carbon b/toolchain/check/testdata/packages/fail_import_default.carbon
new file mode 100644
index 000000000000..805c75e1080d
--- /dev/null
+++ b/toolchain/check/testdata/packages/fail_import_default.carbon
@@ -0,0 +1,48 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+// --- default_api.carbon
+
+package A api;
+
+// CHECK:STDERR: default_api.carbon:[[@LINE+3]]:1: ERROR: File cannot import itself.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+import library default;
+
+// --- default_impl.carbon
+
+package A impl;
+
+// CHECK:STDERR: default_impl.carbon:[[@LINE+3]]:1: ERROR: Explicit import of `api` from `impl` file is redundant with implicit import.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+import library default;
+
+// --- main_import_default.carbon
+
+// CHECK:STDERR: main_import_default.carbon:[[@LINE+3]]:1: ERROR: Explicit import of `api` from `impl` file is redundant with implicit import.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+import library default;
+
+// --- main_lib_import_default.carbon
+
+library "lib" api;
+
+// CHECK:STDERR: main_lib_import_default.carbon:[[@LINE+3]]:1: ERROR: Cannot import `Main//default`.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+import library default;
+
+// CHECK:STDOUT: file "default_api.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "default_impl.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_import_default.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_lib_import_default.carbon" {
+// CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/fail_import_invalid.carbon b/toolchain/check/testdata/packages/fail_import_invalid.carbon
index c8e847933f9c..58ebbaacbb2f 100644
--- a/toolchain/check/testdata/packages/fail_import_invalid.carbon
+++ b/toolchain/check/testdata/packages/fail_import_invalid.carbon
@@ -6,14 +6,28 @@
 
 // --- main.carbon
 
-// CHECK:STDERR: main.carbon:[[@LINE+3]]:1: ERROR: Cannot import `Main` from other packages.
+// CHECK:STDERR: main.carbon:[[@LINE+3]]:1: ERROR: Imports from the current package must omit the package name.
 // CHECK:STDERR: import Main;
 // CHECK:STDERR: ^
 import Main;
 
 // --- main_lib.carbon
 
-// CHECK:STDERR: main_lib.carbon:[[@LINE+3]]:1: ERROR: Cannot import `Main` from other packages.
+// CHECK:STDERR: main_lib.carbon:[[@LINE+3]]:1: ERROR: Imports from the current package must omit the package name.
+// CHECK:STDERR: import Main library "lib";
+// CHECK:STDERR: ^
+import Main library "lib";
+
+// --- not_main.carbon
+
+package NotMain api;
+
+// CHECK:STDERR: not_main.carbon:[[@LINE+3]]:1: ERROR: Cannot import `Main` from other packages.
+// CHECK:STDERR: import Main;
+// CHECK:STDERR: ^
+import Main;
+
+// CHECK:STDERR: not_main.carbon:[[@LINE+3]]:1: ERROR: Cannot import `Main` from other packages.
 // CHECK:STDERR: import Main library "lib";
 // CHECK:STDERR: ^
 import Main library "lib";
@@ -32,9 +46,9 @@ import This;
 package This library "lib" api;
 
 // CHECK:STDERR: this_lib.carbon:[[@LINE+3]]:1: ERROR: File cannot import itself.
-// CHECK:STDERR: import This library "lib";
+// CHECK:STDERR: import library "lib";
 // CHECK:STDERR: ^
-import This library "lib";
+import library "lib";
 
 // --- implicit_api.carbon
 
@@ -62,50 +76,30 @@ package Implicit library "lib" impl;
 // CHECK:STDERR: ^
 import Implicit library "lib";
 
-// --- unknown.carbon
+// --- not_found.carbon
 
-// CHECK:STDERR: unknown.carbon:[[@LINE+3]]:1: ERROR: Imported API not found.
-// CHECK:STDERR: import Unknown;
+// CHECK:STDERR: not_found.carbon:[[@LINE+3]]:1: ERROR: Imported API not found.
+// CHECK:STDERR: import NotFound;
 // CHECK:STDERR: ^
-import Unknown;
+import NotFound;
 
 // CHECK:STDOUT: file "main.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "main_lib.carbon" {
-// CHECK:STDOUT:   %.loc5: String = string_literal "lib"
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "not_main.carbon" {
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "this.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "this_lib.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
-// CHECK:STDOUT:   %.loc7: String = string_literal "lib"
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "implicit_api.carbon" {
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "implicit_impl.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "implicit_lib_api.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "implicit_lib_impl.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
-// CHECK:STDOUT:   %.loc7: String = string_literal "lib"
 // CHECK:STDOUT: }
-// CHECK:STDOUT: file "unknown.carbon" {
+// CHECK:STDOUT: file "not_found.carbon" {
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/fail_import_repeat.carbon b/toolchain/check/testdata/packages/fail_import_repeat.carbon
index 473a28206361..712b2abcd683 100644
--- a/toolchain/check/testdata/packages/fail_import_repeat.carbon
+++ b/toolchain/check/testdata/packages/fail_import_repeat.carbon
@@ -12,39 +12,59 @@ package Api api;
 
 package Api library "lib" api;
 
-// --- import_api.carbon
+// --- main_lib.carbon
+
+library "lib" api;
+
+// --- import.carbon
 
 import Api;
-// CHECK:STDERR: import_api.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
+// CHECK:STDERR: import.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
 // CHECK:STDERR: import Api;
 // CHECK:STDERR: ^
-// CHECK:STDERR: import_api.carbon:[[@LINE-4]]:1: First import here.
+// CHECK:STDERR: import.carbon:[[@LINE-4]]:1: First import here.
 // CHECK:STDERR: import Api;
 // CHECK:STDERR: ^
 import Api;
+
 import Api library "lib";
-// CHECK:STDERR: import_api.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
+// CHECK:STDERR: import.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
 // CHECK:STDERR: import Api library "lib";
 // CHECK:STDERR: ^
-// CHECK:STDERR: import_api.carbon:[[@LINE-4]]:1: First import here.
+// CHECK:STDERR: import.carbon:[[@LINE-4]]:1: First import here.
 // CHECK:STDERR: import Api library "lib";
 // CHECK:STDERR: ^
 import Api library "lib";
 
+import library "lib";
+// CHECK:STDERR: import.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
+// CHECK:STDERR: import library "lib";
+// CHECK:STDERR: ^
+// CHECK:STDERR: import.carbon:[[@LINE-4]]:1: First import here.
+// CHECK:STDERR: import library "lib";
+// CHECK:STDERR: ^
+import library "lib";
+
+// --- default_import.carbon
+
+package Api library "not_default" api;
+
+import library default;
+// CHECK:STDERR: default_import.carbon:[[@LINE+6]]:1: ERROR: Library imported more than once.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+// CHECK:STDERR: default_import.carbon:[[@LINE-4]]:1: First import here.
+// CHECK:STDERR: import library default;
+// CHECK:STDERR: ^
+import library default;
+
 // CHECK:STDOUT: file "api.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "api_lib.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
+// CHECK:STDOUT: file "main_lib.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT:
-// CHECK:STDOUT: file "import_api.carbon" {
-// CHECK:STDOUT:   %.loc10: String = string_literal "lib"
-// CHECK:STDOUT:   %.loc17: String = string_literal "lib"
+// CHECK:STDOUT: file "import.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "default_import.carbon" {
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/fail_package_main.carbon b/toolchain/check/testdata/packages/fail_package_main.carbon
index ee572cbe578f..afb49f7a5b04 100644
--- a/toolchain/check/testdata/packages/fail_package_main.carbon
+++ b/toolchain/check/testdata/packages/fail_package_main.carbon
@@ -6,14 +6,14 @@
 
 // --- main.carbon
 
-// CHECK:STDERR: main.carbon:[[@LINE+3]]:1: ERROR: Default `Main` library must omit `package` directive.
+// CHECK:STDERR: main.carbon:[[@LINE+3]]:1: ERROR: `Main//default` must omit `package` directive.
 // CHECK:STDERR: package Main api;
 // CHECK:STDERR: ^
 package Main api;
 
 // --- main_impl.carbon
 
-// CHECK:STDERR: main_impl.carbon:[[@LINE+3]]:1: ERROR: Default `Main` library must omit `package` directive.
+// CHECK:STDERR: main_impl.carbon:[[@LINE+3]]:1: ERROR: `Main//default` must omit `package` directive.
 // CHECK:STDERR: package Main impl;
 // CHECK:STDERR: ^
 package Main impl;
@@ -21,7 +21,7 @@ package Main impl;
 // --- raw_main.carbon
 
 // `Main` isn't a keyword, so this fails the same way.
-// CHECK:STDERR: raw_main.carbon:[[@LINE+3]]:1: ERROR: Default `Main` library must omit `package` directive.
+// CHECK:STDERR: raw_main.carbon:[[@LINE+3]]:1: ERROR: `Main//default` must omit `package` directive.
 // CHECK:STDERR: package r#Main api;
 // CHECK:STDERR: ^
 package r#Main api;
@@ -39,10 +39,5 @@ package Main library "lib" api;
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "raw_main.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "main_lib.carbon" {
-// CHECK:STDOUT:   %.loc5: String = string_literal "lib"
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/packages/implicit_imports.carbon b/toolchain/check/testdata/packages/implicit_imports.carbon
index 79c96e56e9ef..be20ccb938cc 100644
--- a/toolchain/check/testdata/packages/implicit_imports.carbon
+++ b/toolchain/check/testdata/packages/implicit_imports.carbon
@@ -33,14 +33,19 @@ package WithImpl library "lib" api;
 
 package WithImpl library "lib" impl;
 
+// --- main.carbon
+
+// --- main_lib.carbon
+
+library "lib" api;
+
+// --- main_lib_impl.carbon
+
+library "lib" impl;
+
 // CHECK:STDOUT: file "api_only.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "api_only_lib.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "with_impl_api.carbon" {
 // CHECK:STDOUT: }
@@ -48,17 +53,13 @@ package WithImpl library "lib" impl;
 // CHECK:STDOUT: }
 // CHECK:STDOUT: file "with_impl_impl_extra.carbon" {
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "with_impl_lib_api.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
 // CHECK:STDOUT: }
-// CHECK:STDOUT: constants {
-// CHECK:STDOUT:   %.1: type = ptr_type String
-// CHECK:STDOUT: }
-// CHECK:STDOUT:
 // CHECK:STDOUT: file "with_impl_lib_impl.carbon" {
-// CHECK:STDOUT:   %.loc2: String = string_literal "lib"
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_lib.carbon" {
+// CHECK:STDOUT: }
+// CHECK:STDOUT: file "main_lib_impl.carbon" {
 // CHECK:STDOUT: }
diff --git a/toolchain/diagnostics/diagnostic_kind.def b/toolchain/diagnostics/diagnostic_kind.def
index 760df86293bd..280712c32344 100644
--- a/toolchain/diagnostics/diagnostic_kind.def
+++ b/toolchain/diagnostics/diagnostic_kind.def
@@ -86,8 +86,10 @@ CARBON_DIAGNOSTIC_KIND(FirstDecl)
 CARBON_DIAGNOSTIC_KIND(FirstNonCommentLine)
 CARBON_DIAGNOSTIC_KIND(PackageTooLate)
 CARBON_DIAGNOSTIC_KIND(ImportTooLate)
-CARBON_DIAGNOSTIC_KIND(ExpectedIdentifierAfterKeyword)
+CARBON_DIAGNOSTIC_KIND(ExpectedIdentifierAfterPackage)
+CARBON_DIAGNOSTIC_KIND(ExpectedIdentifierAfterImport)
 CARBON_DIAGNOSTIC_KIND(ExpectedLibraryName)
+CARBON_DIAGNOSTIC_KIND(ExpectedLibraryNameOrDefault)
 CARBON_DIAGNOSTIC_KIND(MissingLibraryKeyword)
 CARBON_DIAGNOSTIC_KIND(ExpectedApiOrImpl)
 
@@ -122,6 +124,8 @@ CARBON_DIAGNOSTIC_KIND(ImportCycleDetected)
 CARBON_DIAGNOSTIC_KIND(ExplicitMainPackage)
 CARBON_DIAGNOSTIC_KIND(ExplicitMainLibrary)
 CARBON_DIAGNOSTIC_KIND(ImportMainPackage)
+CARBON_DIAGNOSTIC_KIND(ImportMainDefaultLibrary)
+CARBON_DIAGNOSTIC_KIND(ImportCurrentPackageByName)
 CARBON_DIAGNOSTIC_KIND(ImportSelf)
 CARBON_DIAGNOSTIC_KIND(ExplicitImportApi)
 CARBON_DIAGNOSTIC_KIND(RepeatedImport)
diff --git a/toolchain/parse/handle_decl_scope_loop.cpp b/toolchain/parse/handle_decl_scope_loop.cpp
index c9ecca9df885..5bcf02087395 100644
--- a/toolchain/parse/handle_decl_scope_loop.cpp
+++ b/toolchain/parse/handle_decl_scope_loop.cpp
@@ -30,11 +30,15 @@ auto HandleDeclScopeLoop(Context& context) -> void {
       context.PopAndDiscardState();
       return;
     }
-    // `import` and `package` manage their packaging state.
+    // `import`, `library`, and `package` manage their packaging state.
     case Lex::TokenKind::Import: {
       context.PushState(State::Import);
       return;
     }
+    case Lex::TokenKind::Library: {
+      context.PushState(State::Library);
+      return;
+    }
     case Lex::TokenKind::Package: {
       context.PushState(State::Package);
       return;
diff --git a/toolchain/parse/handle_import_and_package.cpp b/toolchain/parse/handle_import_and_package.cpp
index 1345a8c9c28f..506739d22dc3 100644
--- a/toolchain/parse/handle_import_and_package.cpp
+++ b/toolchain/parse/handle_import_and_package.cpp
@@ -5,113 +5,165 @@
 #include "toolchain/base/value_store.h"
 #include "toolchain/lex/tokenized_buffer.h"
 #include "toolchain/parse/context.h"
+#include "toolchain/parse/node_kind.h"
 
 namespace Carbon::Parse {
 
-// Provides error exiting logic for `import`/`package`, skipping to the semi.
-static auto ExitOnParseError(Context& context, Context::StateStackEntry state,
-                             NodeKind directive) {
+// Provides common error exiting logic that skips to the semi, if present.
+static auto OnParseError(Context& context, Context::StateStackEntry state,
+                         NodeKind directive) -> void {
   auto semi_token = context.SkipPastLikelyEnd(state.token);
   return context.AddNode(directive, semi_token ? *semi_token : state.token,
                          state.subtree_start,
                          /*has_error=*/true);
 }
 
-// Handles the main parsing of `import`/`package`. It's expected that the
-// introducer is already added.
-static auto HandleImportAndPackage(Context& context,
+// Handles parsing of the library name. Returns the name's ID on success, which
+// may be invalid for `default`.
+static auto HandleLibraryName(Context& context, bool accept_default)
+    -> std::optional<StringLiteralId> {
+  if (auto library_name_token =
+          context.ConsumeIf(Lex::TokenKind::StringLiteral)) {
+    context.AddLeafNode(NodeKind::LibraryName, *library_name_token);
+    return context.tokens().GetStringLiteral(*library_name_token);
+  }
+
+  if (accept_default) {
+    if (auto default_token = context.ConsumeIf(Lex::TokenKind::Default)) {
+      context.AddLeafNode(NodeKind::DefaultLibrary, *default_token);
+      return StringLiteralId::Invalid;
+    }
+  }
+
+  CARBON_DIAGNOSTIC(
+      ExpectedLibraryNameOrDefault, Error,
+      "Expected `default` or a string literal to specify the library name.");
+  CARBON_DIAGNOSTIC(ExpectedLibraryName, Error,
+                    "Expected a string literal to specify the library name.");
+  context.emitter().Emit(*context.position(), accept_default
+                                                  ? ExpectedLibraryNameOrDefault
+                                                  : ExpectedLibraryName);
+  return std::nullopt;
+}
+
+// Returns whether `api` or `impl` is provided, or prints an error and returns
+// nullopt.
+static auto HandleApiOrImpl(Context& context)
+    -> std::optional<Tree::ApiOrImpl> {
+  switch (context.PositionKind()) {
+    case Lex::TokenKind::Api: {
+      context.AddLeafNode(NodeKind::PackageApi,
+                          context.ConsumeChecked(Lex::TokenKind::Api));
+      return Tree::ApiOrImpl::Api;
+      break;
+    }
+    case Lex::TokenKind::Impl: {
+      context.AddLeafNode(NodeKind::PackageImpl,
+                          context.ConsumeChecked(Lex::TokenKind::Impl));
+      return Tree::ApiOrImpl::Impl;
+      break;
+    }
+    default: {
+      CARBON_DIAGNOSTIC(ExpectedApiOrImpl, Error, "Expected `api` or `impl`.");
+      context.emitter().Emit(*context.position(), ExpectedApiOrImpl);
+      return std::nullopt;
+    }
+  }
+}
+
+// Handles everything after the directive's introducer.
+static auto HandleDirectiveContent(Context& context,
                                    Context::StateStackEntry state,
-                                   NodeKind directive, bool is_package)
+                                   NodeKind directive,
+                                   llvm::function_ref<void()> on_parse_error)
     -> void {
   Tree::PackagingNames names{.node = Node(state.subtree_start)};
-  if (auto package_name_token = context.ConsumeIf(Lex::TokenKind::Identifier)) {
-    names.package_id = context.tokens().GetIdentifier(*package_name_token);
-    context.AddLeafNode(NodeKind::Name, *package_name_token);
-  } else {
-    CARBON_DIAGNOSTIC(ExpectedIdentifierAfterKeyword, Error,
-                      "Expected identifier after `{0}`.", Lex::TokenKind);
-    context.emitter().Emit(*context.position(), ExpectedIdentifierAfterKeyword,
-                           context.tokens().GetKind(state.token));
-    ExitOnParseError(context, state, directive);
-    return;
-  }
-
-  if (auto library_token = context.ConsumeIf(Lex::TokenKind::Library)) {
-    auto library_start = context.tree().size();
-
-    if (auto library_name_token =
-            context.ConsumeIf(Lex::TokenKind::StringLiteral)) {
-      names.library_id = context.tokens().GetStringLiteral(*library_name_token);
-      context.AddLeafNode(NodeKind::Literal, *library_name_token);
-    } else {
-      CARBON_DIAGNOSTIC(
-          ExpectedLibraryName, Error,
-          "Expected a string literal to specify the library name.");
-      context.emitter().Emit(*context.position(), ExpectedLibraryName);
-      ExitOnParseError(context, state, directive);
+  if (directive != NodeKind::LibraryDirective) {
+    if (auto package_name_token =
+            context.ConsumeIf(Lex::TokenKind::Identifier)) {
+      names.package_id = context.tokens().GetIdentifier(*package_name_token);
+      context.AddLeafNode(NodeKind::PackageName, *package_name_token);
+    } else if (directive == NodeKind::PackageDirective ||
+               !context.PositionIs(Lex::TokenKind::Library)) {
+      CARBON_DIAGNOSTIC(ExpectedIdentifierAfterPackage, Error,
+                        "Expected identifier after `package`.");
+      CARBON_DIAGNOSTIC(ExpectedIdentifierAfterImport, Error,
+                        "Expected identifier or `library` after `import`.");
+      context.emitter().Emit(*context.position(),
+                             directive == NodeKind::PackageDirective
+                                 ? ExpectedIdentifierAfterPackage
+                                 : ExpectedIdentifierAfterImport);
+      on_parse_error();
       return;
     }
-
-    context.AddNode(NodeKind::Library, *library_token, library_start,
-                    /*has_error=*/false);
   }
 
-  auto next_kind = context.PositionKind();
-  if (!names.library_id.is_valid() &&
-      next_kind == Lex::TokenKind::StringLiteral) {
-    // If we come acroess a string literal and we didn't parse `library
-    // "..."` yet, then most probably the user forgot to add `library`
-    // before the library name.
-    CARBON_DIAGNOSTIC(MissingLibraryKeyword, Error,
-                      "Missing `library` keyword.");
-    context.emitter().Emit(*context.position(), MissingLibraryKeyword);
-    ExitOnParseError(context, state, directive);
-    return;
-  }
-
-  Tree::ApiOrImpl api_or_impl;
-  if (is_package) {
-    switch (next_kind) {
-      case Lex::TokenKind::Api: {
-        context.AddLeafNode(NodeKind::PackageApi, context.Consume());
-        api_or_impl = Tree::ApiOrImpl::Api;
-        break;
-      }
-      case Lex::TokenKind::Impl: {
-        context.AddLeafNode(NodeKind::PackageImpl, context.Consume());
-        api_or_impl = Tree::ApiOrImpl::Impl;
-        break;
-      }
-      default: {
-        CARBON_DIAGNOSTIC(ExpectedApiOrImpl, Error,
-                          "Expected `api` or `impl`.");
-        context.emitter().Emit(*context.position(), ExpectedApiOrImpl);
-        ExitOnParseError(context, state, directive);
+  // Parse the optional library keyword.
+  bool accept_default = !names.package_id.is_valid();
+  if (directive == NodeKind::LibraryDirective) {
+    auto library_id = HandleLibraryName(context, accept_default);
+    if (!library_id) {
+      on_parse_error();
+      return;
+    }
+    names.library_id = *library_id;
+  } else {
+    auto next_kind = context.PositionKind();
+    if (next_kind == Lex::TokenKind::Library) {
+      auto library_token = context.ConsumeChecked(Lex::TokenKind::Library);
+      auto library_subtree_start = context.tree().size();
+      auto library_id = HandleLibraryName(context, accept_default);
+      if (!library_id) {
+        on_parse_error();
         return;
       }
+      names.library_id = *library_id;
+      context.AddNode(NodeKind::LibrarySpecifier, library_token,
+                      library_subtree_start,
+                      /*has_error=*/false);
+    } else if (next_kind == Lex::TokenKind::StringLiteral ||
+               (accept_default && next_kind == Lex::TokenKind::Default)) {
+      // If we come across a string literal and we didn't parse `library
+      // "..."` yet, then most probably the user forgot to add `library`
+      // before the library name.
+      CARBON_DIAGNOSTIC(MissingLibraryKeyword, Error,
+                        "Missing `library` keyword.");
+      context.emitter().Emit(*context.position(), MissingLibraryKeyword);
+      on_parse_error();
+      return;
     }
   }
 
-  if (!context.PositionIs(Lex::TokenKind::Semi)) {
-    context.EmitExpectedDeclSemi(context.tokens().GetKind(state.token));
-    ExitOnParseError(context, state, directive);
-    return;
+  std::optional<Tree::ApiOrImpl> api_or_impl;
+  if (directive != NodeKind::ImportDirective) {
+    api_or_impl = HandleApiOrImpl(context);
+    if (!api_or_impl) {
+      on_parse_error();
+      return;
+    }
   }
 
-  if (is_package) {
-    context.set_packaging_directive(names, api_or_impl);
+  if (auto semi = context.ConsumeIf(Lex::TokenKind::Semi)) {
+    if (directive == NodeKind::ImportDirective) {
+      context.AddImport(names);
+    } else {
+      context.set_packaging_directive(names, *api_or_impl);
+    }
+
+    context.AddNode(directive, *semi, state.subtree_start, state.has_error);
   } else {
-    context.AddImport(names);
+    context.EmitExpectedDeclSemi(context.tokens().GetKind(state.token));
+    on_parse_error();
   }
-
-  context.AddNode(directive, context.Consume(), state.subtree_start,
-                  state.has_error);
 }
 
 auto HandleImport(Context& context) -> void {
   auto state = context.PopState();
 
-  auto intro_token = context.Consume();
+  auto directive = NodeKind::ImportDirective;
+  auto on_parse_error = [&] { OnParseError(context, state, directive); };
+
+  auto intro_token = context.ConsumeChecked(Lex::TokenKind::Import);
   context.AddLeafNode(NodeKind::ImportIntroducer, intro_token);
 
   switch (context.packaging_state()) {
@@ -121,8 +173,7 @@ auto HandleImport(Context& context) -> void {
       [[clang::fallthrough]];
 
     case Context::PackagingState::InImports:
-      HandleImportAndPackage(context, state, NodeKind::ImportDirective,
-                             /*is_package=*/false);
+      HandleDirectiveContent(context, state, directive, on_parse_error);
       break;
 
     case Context::PackagingState::AfterNonPackagingDecl: {
@@ -137,42 +188,60 @@ auto HandleImport(Context& context) -> void {
           .Build(intro_token, ImportTooLate)
           .Note(context.first_non_packaging_token(), FirstDecl)
           .Emit();
-      ExitOnParseError(context, state, NodeKind::ImportDirective);
+      on_parse_error();
       break;
     }
     case Context::PackagingState::InImportsAfterNonPackagingDecl:
       // There is a sequential block of misplaced `import` statements, which can
       // occur if a declaration is added above `import`s. Avoid duplicate
       // warnings.
-      ExitOnParseError(context, state, NodeKind::ImportDirective);
+      on_parse_error();
       break;
   }
 }
 
-auto HandlePackage(Context& context) -> void {
+// Handles common logic for `package` and `library`.
+static auto HandlePackageAndLibraryDirectives(Context& context,
+                                              Lex::TokenKind intro_token_kind,
+                                              NodeKind intro,
+                                              NodeKind directive) -> void {
   auto state = context.PopState();
 
-  auto intro_token = context.Consume();
-  context.AddLeafNode(NodeKind::PackageIntroducer, intro_token);
+  auto on_parse_error = [&] { OnParseError(context, state, directive); };
+
+  auto intro_token = context.ConsumeChecked(intro_token_kind);
+  context.AddLeafNode(intro, intro_token);
 
   if (intro_token != Lex::Token::FirstNonCommentToken) {
-    CARBON_DIAGNOSTIC(
-        PackageTooLate, Error,
-        "The `package` directive must be the first non-comment line.");
+    CARBON_DIAGNOSTIC(PackageTooLate, Error,
+                      "The `{0}` directive must be the first non-comment line.",
+                      Lex::TokenKind);
     CARBON_DIAGNOSTIC(FirstNonCommentLine, Note,
                       "First non-comment line is here.");
     context.emitter()
-        .Build(intro_token, PackageTooLate)
+        .Build(intro_token, PackageTooLate, intro_token_kind)
         .Note(Lex::Token::FirstNonCommentToken, FirstNonCommentLine)
         .Emit();
-    ExitOnParseError(context, state, NodeKind::PackageDirective);
+    on_parse_error();
     return;
   }
 
-  // `package` is no longer allowed, but `import` may repeat.
+  // `package`/`library` is no longer allowed, but `import` may repeat.
   context.set_packaging_state(Context::PackagingState::InImports);
-  HandleImportAndPackage(context, state, NodeKind::PackageDirective,
-                         /*is_package=*/true);
+
+  HandleDirectiveContent(context, state, directive, on_parse_error);
+}
+
+auto HandlePackage(Context& context) -> void {
+  HandlePackageAndLibraryDirectives(context, Lex::TokenKind::Package,
+                                    NodeKind::PackageIntroducer,
+                                    NodeKind::PackageDirective);
+}
+
+auto HandleLibrary(Context& context) -> void {
+  HandlePackageAndLibraryDirectives(context, Lex::TokenKind::Library,
+                                    NodeKind::LibraryIntroducer,
+                                    NodeKind::LibraryDirective);
 }
 
 }  // namespace Carbon::Parse
diff --git a/toolchain/parse/node_kind.def b/toolchain/parse/node_kind.def
index 0a8a543b21d4..19157ac014bd 100644
--- a/toolchain/parse/node_kind.def
+++ b/toolchain/parse/node_kind.def
@@ -95,15 +95,14 @@ CARBON_PARSE_NODE_KIND_CHILD_COUNT(NameExpr, 0, CARBON_TOKEN(Identifier))
 
 // ----------------------------------------------------------------------------
 
-// `library`:
-//   _external_: Literal
-// Library
-CARBON_PARSE_NODE_KIND_CHILD_COUNT(Library, 1, CARBON_TOKEN(Library))
+// The name of a package or library for `package`, `import`, and `library`.
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(PackageName, 0, CARBON_TOKEN(Identifier))
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(LibraryName, 0, CARBON_TOKEN(StringLiteral))
 
 // `package`:
 //   PackageIntroducer
-//   _external_: Name
-//   _optional_ _external_: Library
+//   _optional_ _external_: PackageName
+//   _optional_ _external_: LibrarySpecifier
 //   PackageApi or PackageImpl
 // PackageDirective
 CARBON_PARSE_NODE_KIND_CHILD_COUNT(PackageIntroducer, 0, CARBON_TOKEN(Package))
@@ -115,13 +114,27 @@ CARBON_PARSE_NODE_KIND_BRACKET(PackageDirective, PackageIntroducer,
 
 // `import`:
 //   ImportIntroducer
-//   _external_: Name
-//   _optional_ _external_: Library
+//   _optional_ _external_: PackageName
+//   _optional_ _external_: LibrarySpecifier
 // ImportDirective
 CARBON_PARSE_NODE_KIND_CHILD_COUNT(ImportIntroducer, 0, CARBON_TOKEN(Import))
 CARBON_PARSE_NODE_KIND_BRACKET(ImportDirective, ImportIntroducer,
                                CARBON_TOKEN(Semi)
                                    CARBON_IF_ERROR(CARBON_TOKEN(Import)))
+// `library` as directive:
+//   LibraryIntroducer
+//   DefaultLibrary or _external_: LibraryName
+// LibraryDirective
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(DefaultLibrary, 0, CARBON_TOKEN(Default))
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(LibraryIntroducer, 0, CARBON_TOKEN(Library))
+CARBON_PARSE_NODE_KIND_BRACKET(LibraryDirective, LibraryIntroducer,
+                               CARBON_TOKEN(Semi)
+                                   CARBON_IF_ERROR(CARBON_TOKEN(Library)))
+
+// `library` in `package` or `import`:
+//   _external_: LibraryName
+// LibrarySpecifier
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(LibrarySpecifier, 1, CARBON_TOKEN(Library))
 
 // `namespace`:
 //   NamespaceStart
diff --git a/toolchain/parse/state.def b/toolchain/parse/state.def
index a8737ac4913d..d99f6e46acc4 100644
--- a/toolchain/parse/state.def
+++ b/toolchain/parse/state.def
@@ -591,6 +591,12 @@ CARBON_PARSE_STATE(FunctionDefinitionFinish)
 //   (state done)
 CARBON_PARSE_STATE(Import)
 
+// Handles `library` in directive form.
+//
+// Always:
+//   (state done)
+CARBON_PARSE_STATE(Library)
+
 // Handles `namespace`.
 //
 // namespace ...
diff --git a/toolchain/parse/testdata/packages/import/after_import.carbon b/toolchain/parse/testdata/packages/import/after_import.carbon
index 7f14322681e6..8a16817cf602 100644
--- a/toolchain/parse/testdata/packages/import/after_import.carbon
+++ b/toolchain/parse/testdata/packages/import/after_import.carbon
@@ -11,10 +11,10 @@ import B;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'A'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'B'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'B'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/after_package.carbon b/toolchain/parse/testdata/packages/import/after_package.carbon
index 7f859725ae1e..fe482c558a9f 100644
--- a/toolchain/parse/testdata/packages/import/after_package.carbon
+++ b/toolchain/parse/testdata/packages/import/after_package.carbon
@@ -12,11 +12,11 @@ import B;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'A'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
 // CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 4},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'B'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'B'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/basic.carbon b/toolchain/parse/testdata/packages/import/basic.carbon
index 4cfb8a73dbb5..b37335dc3c7f 100644
--- a/toolchain/parse/testdata/packages/import/basic.carbon
+++ b/toolchain/parse/testdata/packages/import/basic.carbon
@@ -10,7 +10,7 @@ import Geometry;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/current_package_library.carbon b/toolchain/parse/testdata/packages/import/current_package_library.carbon
new file mode 100644
index 000000000000..ab955a7e046c
--- /dev/null
+++ b/toolchain/parse/testdata/packages/import/current_package_library.carbon
@@ -0,0 +1,32 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+// --- default.carbon
+
+import library default;
+
+// --- named.carbon
+
+import library "Shapes";
+
+// CHECK:STDOUT: - filename: default.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:         {kind: 'DefaultLibrary', text: 'default'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: named.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"Shapes"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_extra_string.carbon b/toolchain/parse/testdata/packages/import/fail_extra_string.carbon
index 6d523bad9a56..b58173ac77d4 100644
--- a/toolchain/parse/testdata/packages/import/fail_extra_string.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_extra_string.carbon
@@ -13,9 +13,9 @@ import Foo library "bar" "baz";
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Foo'},
-// CHECK:STDOUT:         {kind: 'Literal', text: '"bar"'},
-// CHECK:STDOUT:       {kind: 'Library', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Foo'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"bar"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', has_error: yes, subtree_size: 5},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_library_is_identifier.carbon b/toolchain/parse/testdata/packages/import/fail_library_is_identifier.carbon
index e2a745738e28..911a3a43a50c 100644
--- a/toolchain/parse/testdata/packages/import/fail_library_is_identifier.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_library_is_identifier.carbon
@@ -13,7 +13,7 @@ import Geometry library Shapes;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_library_skips_name.carbon b/toolchain/parse/testdata/packages/import/fail_library_skips_name.carbon
deleted file mode 100644
index 0bad8f5bcce7..000000000000
--- a/toolchain/parse/testdata/packages/import/fail_library_skips_name.carbon
+++ /dev/null
@@ -1,18 +0,0 @@
-// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
-// Exceptions. See /LICENSE for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-// AUTOUPDATE
-
-// CHECK:STDERR: fail_library_skips_name.carbon:[[@LINE+3]]:8: ERROR: Expected identifier after `import`.
-// CHECK:STDERR: import library "Shapes";
-// CHECK:STDERR:        ^
-import library "Shapes";
-
-// CHECK:STDOUT: - filename: fail_library_skips_name.carbon
-// CHECK:STDOUT:   parse_tree: [
-// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
-// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', has_error: yes, subtree_size: 2},
-// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
-// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_name_is_keyword.carbon b/toolchain/parse/testdata/packages/import/fail_name_is_keyword.carbon
index 27d3b2950004..bc17d80201a6 100644
--- a/toolchain/parse/testdata/packages/import/fail_name_is_keyword.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_name_is_keyword.carbon
@@ -4,7 +4,7 @@
 //
 // AUTOUPDATE
 
-// CHECK:STDERR: fail_name_is_keyword.carbon:[[@LINE+3]]:8: ERROR: Expected identifier after `import`.
+// CHECK:STDERR: fail_name_is_keyword.carbon:[[@LINE+3]]:8: ERROR: Expected identifier or `library` after `import`.
 // CHECK:STDERR: import fn;
 // CHECK:STDERR:        ^
 import fn;
diff --git a/toolchain/parse/testdata/packages/import/fail_no_name.carbon b/toolchain/parse/testdata/packages/import/fail_no_name.carbon
index 1b867b767483..4d52842078a3 100644
--- a/toolchain/parse/testdata/packages/import/fail_no_name.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_no_name.carbon
@@ -4,7 +4,7 @@
 //
 // AUTOUPDATE
 
-// CHECK:STDERR: fail_no_name.carbon:[[@LINE+3]]:7: ERROR: Expected identifier after `import`.
+// CHECK:STDERR: fail_no_name.carbon:[[@LINE+3]]:7: ERROR: Expected identifier or `library` after `import`.
 // CHECK:STDERR: import;
 // CHECK:STDERR:       ^
 import;
diff --git a/toolchain/parse/testdata/packages/import/fail_no_semi.carbon b/toolchain/parse/testdata/packages/import/fail_no_semi.carbon
index 93580a7f2720..fca391a5aa48 100644
--- a/toolchain/parse/testdata/packages/import/fail_no_semi.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_no_semi.carbon
@@ -13,7 +13,7 @@ import Geometry
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: 'import', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_omit_library_keyword.carbon b/toolchain/parse/testdata/packages/import/fail_omit_library_keyword.carbon
index 815fb103cd4f..1fea016b2f3a 100644
--- a/toolchain/parse/testdata/packages/import/fail_omit_library_keyword.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_omit_library_keyword.carbon
@@ -13,7 +13,7 @@ import Geometry "Shapes";
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/fail_type.carbon b/toolchain/parse/testdata/packages/import/fail_type.carbon
index 6fa8f8d5c475..4b9f180cd299 100644
--- a/toolchain/parse/testdata/packages/import/fail_type.carbon
+++ b/toolchain/parse/testdata/packages/import/fail_type.carbon
@@ -13,7 +13,7 @@ import Geometry api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/library.carbon b/toolchain/parse/testdata/packages/import/library.carbon
index 3d5b756ce3a8..c43f73b11f60 100644
--- a/toolchain/parse/testdata/packages/import/library.carbon
+++ b/toolchain/parse/testdata/packages/import/library.carbon
@@ -10,9 +10,9 @@ import Geometry library "Shapes";
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
-// CHECK:STDOUT:         {kind: 'Literal', text: '"Shapes"'},
-// CHECK:STDOUT:       {kind: 'Library', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"Shapes"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 5},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/import/ordering.carbon b/toolchain/parse/testdata/packages/import/ordering.carbon
new file mode 100644
index 000000000000..284efbf995a0
--- /dev/null
+++ b/toolchain/parse/testdata/packages/import/ordering.carbon
@@ -0,0 +1,58 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+// --- after_import.carbon
+
+import A;
+import B;
+
+// --- after_library.carbon
+
+library "A" api;
+
+import B;
+
+// --- after_package.carbon
+
+package A api;
+
+import B;
+
+// CHECK:STDOUT: - filename: after_import.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'B'},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: after_library.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:       {kind: 'LibraryName', text: '"A"'},
+// CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'B'},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: after_package.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
+// CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
+// CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'B'},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/library/basic.carbon b/toolchain/parse/testdata/packages/library/basic.carbon
new file mode 100644
index 000000000000..9c24f1b67797
--- /dev/null
+++ b/toolchain/parse/testdata/packages/library/basic.carbon
@@ -0,0 +1,32 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+// --- default.carbon
+
+library default api;
+
+// --- named.carbon
+
+library "Shapes" impl;
+
+// CHECK:STDOUT: - filename: default.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:       {kind: 'DefaultLibrary', text: 'default'},
+// CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: named.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:       {kind: 'LibraryName', text: '"Shapes"'},
+// CHECK:STDOUT:       {kind: 'PackageImpl', text: 'impl'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/library/fail_invalid_name.carbon b/toolchain/parse/testdata/packages/library/fail_invalid_name.carbon
new file mode 100644
index 000000000000..6739686812f1
--- /dev/null
+++ b/toolchain/parse/testdata/packages/library/fail_invalid_name.carbon
@@ -0,0 +1,78 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+// --- identifier.carbon
+
+// CHECK:STDERR: identifier.carbon:[[@LINE+3]]:9: ERROR: Expected `default` or a string literal to specify the library name.
+// CHECK:STDERR: library Shapes api;
+// CHECK:STDERR:         ^
+library Shapes api;
+
+// --- raw_identifier.carbon
+
+// CHECK:STDERR: raw_identifier.carbon:[[@LINE+3]]:9: ERROR: Expected `default` or a string literal to specify the library name.
+// CHECK:STDERR: library r#default api;
+// CHECK:STDERR:         ^
+library r#default api;
+
+// --- missing.carbon
+
+// CHECK:STDERR: missing.carbon:[[@LINE+3]]:8: ERROR: Expected `default` or a string literal to specify the library name.
+// CHECK:STDERR: library;
+// CHECK:STDERR:        ^
+library;
+
+// --- missing_with_api.carbon
+
+// CHECK:STDERR: missing_with_api.carbon:[[@LINE+3]]:9: ERROR: Expected `default` or a string literal to specify the library name.
+// CHECK:STDERR: library api;
+// CHECK:STDERR:         ^
+library api;
+
+// --- no_semi.carbon
+
+library "NoSemi" api
+
+// CHECK:STDERR: no_semi.carbon:[[@LINE+39]]:21: ERROR: `library` declarations must end with a `;`.
+// CHECK:STDERR: // CHECK:STDOUT:   ]
+// CHECK:STDERR:                     ^
+// CHECK:STDOUT: - filename: identifier.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', has_error: yes, subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: raw_identifier.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', has_error: yes, subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: missing.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', has_error: yes, subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: missing_with_api.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', has_error: yes, subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: no_semi.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:       {kind: 'LibraryName', text: '"NoSemi"'},
+// CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: 'library', has_error: yes, subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/library/fail_too_late.carbon b/toolchain/parse/testdata/packages/library/fail_too_late.carbon
new file mode 100644
index 000000000000..54ea670b4f97
--- /dev/null
+++ b/toolchain/parse/testdata/packages/library/fail_too_late.carbon
@@ -0,0 +1,26 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+
+import Geometry;
+
+// CHECK:STDERR: fail_too_late.carbon:[[@LINE+6]]:1: ERROR: The `library` directive must be the first non-comment line.
+// CHECK:STDERR: library "Shapes" api;
+// CHECK:STDERR: ^
+// CHECK:STDERR: fail_too_late.carbon:[[@LINE-5]]:1: First non-comment line is here.
+// CHECK:STDERR: import Geometry;
+// CHECK:STDERR: ^
+library "Shapes" api;
+
+// CHECK:STDOUT: - filename: fail_too_late.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
+// CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
+// CHECK:STDOUT:       {kind: 'LibraryIntroducer', text: 'library'},
+// CHECK:STDOUT:     {kind: 'LibraryDirective', text: ';', has_error: yes, subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/package/api.carbon b/toolchain/parse/testdata/packages/package/api.carbon
index 3ac51c66dbdc..420ff101e435 100644
--- a/toolchain/parse/testdata/packages/package/api.carbon
+++ b/toolchain/parse/testdata/packages/package/api.carbon
@@ -10,7 +10,7 @@ package Geometry api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 4},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
diff --git a/toolchain/parse/testdata/packages/package/api_library.carbon b/toolchain/parse/testdata/packages/package/api_library.carbon
index 4ab898ef3034..b20bbb981a2a 100644
--- a/toolchain/parse/testdata/packages/package/api_library.carbon
+++ b/toolchain/parse/testdata/packages/package/api_library.carbon
@@ -10,9 +10,9 @@ package Geometry library "Shapes" api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
-// CHECK:STDOUT:         {kind: 'Literal', text: '"Shapes"'},
-// CHECK:STDOUT:       {kind: 'Library', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"Shapes"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
 // CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 6},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
diff --git a/toolchain/parse/testdata/packages/package/fail_after_import.carbon b/toolchain/parse/testdata/packages/package/fail_after_import.carbon
index 843dfa929f67..bb3b1e20407d 100644
--- a/toolchain/parse/testdata/packages/package/fail_after_import.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_after_import.carbon
@@ -18,7 +18,7 @@ package B api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'ImportIntroducer', text: 'import'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'A'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
 // CHECK:STDOUT:     {kind: 'ImportDirective', text: ';', subtree_size: 3},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', has_error: yes, subtree_size: 2},
diff --git a/toolchain/parse/testdata/packages/package/fail_after_package.carbon b/toolchain/parse/testdata/packages/package/fail_after_package.carbon
index 341c0b2a1315..a9e4fdecd434 100644
--- a/toolchain/parse/testdata/packages/package/fail_after_package.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_after_package.carbon
@@ -17,7 +17,7 @@ package B api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'A'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'A'},
 // CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 4},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
diff --git a/toolchain/parse/testdata/packages/package/fail_extra_string.carbon b/toolchain/parse/testdata/packages/package/fail_extra_string.carbon
index 9432f4c7ee34..0de4de74db94 100644
--- a/toolchain/parse/testdata/packages/package/fail_extra_string.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_extra_string.carbon
@@ -13,9 +13,9 @@ package Foo library "bar" "baz";
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Foo'},
-// CHECK:STDOUT:         {kind: 'Literal', text: '"bar"'},
-// CHECK:STDOUT:       {kind: 'Library', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Foo'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"bar"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', has_error: yes, subtree_size: 5},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/package/fail_library_is_identifier.carbon b/toolchain/parse/testdata/packages/package/fail_library_is_identifier.carbon
index 03f76bb14973..501c5c532b82 100644
--- a/toolchain/parse/testdata/packages/package/fail_library_is_identifier.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_library_is_identifier.carbon
@@ -13,7 +13,7 @@ package Geometry library Shapes api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/package/fail_no_semi.carbon b/toolchain/parse/testdata/packages/package/fail_no_semi.carbon
index b9aee3f1bf26..fc3f1d0c3a20 100644
--- a/toolchain/parse/testdata/packages/package/fail_no_semi.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_no_semi.carbon
@@ -13,7 +13,7 @@ package Geometry api
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:       {kind: 'PackageApi', text: 'api'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: 'package', has_error: yes, subtree_size: 4},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
diff --git a/toolchain/parse/testdata/packages/package/fail_no_type.carbon b/toolchain/parse/testdata/packages/package/fail_no_type.carbon
index e574d90e24e8..ad70261b4d29 100644
--- a/toolchain/parse/testdata/packages/package/fail_no_type.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_no_type.carbon
@@ -13,7 +13,7 @@ package Geometry;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/package/fail_omit_library_keyword.carbon b/toolchain/parse/testdata/packages/package/fail_omit_library_keyword.carbon
index 744b5da749f8..a2035a7befa4 100644
--- a/toolchain/parse/testdata/packages/package/fail_omit_library_keyword.carbon
+++ b/toolchain/parse/testdata/packages/package/fail_omit_library_keyword.carbon
@@ -13,7 +13,7 @@ package Geometry "Shapes" api;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', has_error: yes, subtree_size: 3},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
 // CHECK:STDOUT:   ]
diff --git a/toolchain/parse/testdata/packages/package/impl.carbon b/toolchain/parse/testdata/packages/package/impl.carbon
index d840b5fadc05..a8414405e701 100644
--- a/toolchain/parse/testdata/packages/package/impl.carbon
+++ b/toolchain/parse/testdata/packages/package/impl.carbon
@@ -10,7 +10,7 @@ package Geometry impl;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
 // CHECK:STDOUT:       {kind: 'PackageImpl', text: 'impl'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 4},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
diff --git a/toolchain/parse/testdata/packages/package/impl_library.carbon b/toolchain/parse/testdata/packages/package/impl_library.carbon
index 878b96811005..f1dfc524cf3d 100644
--- a/toolchain/parse/testdata/packages/package/impl_library.carbon
+++ b/toolchain/parse/testdata/packages/package/impl_library.carbon
@@ -10,9 +10,9 @@ package Geometry library "Shapes" impl;
 // CHECK:STDOUT:   parse_tree: [
 // CHECK:STDOUT:     {kind: 'FileStart', text: ''},
 // CHECK:STDOUT:       {kind: 'PackageIntroducer', text: 'package'},
-// CHECK:STDOUT:       {kind: 'Name', text: 'Geometry'},
-// CHECK:STDOUT:         {kind: 'Literal', text: '"Shapes"'},
-// CHECK:STDOUT:       {kind: 'Library', text: 'library', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'PackageName', text: 'Geometry'},
+// CHECK:STDOUT:         {kind: 'LibraryName', text: '"Shapes"'},
+// CHECK:STDOUT:       {kind: 'LibrarySpecifier', text: 'library', subtree_size: 2},
 // CHECK:STDOUT:       {kind: 'PackageImpl', text: 'impl'},
 // CHECK:STDOUT:     {kind: 'PackageDirective', text: ';', subtree_size: 6},
 // CHECK:STDOUT:     {kind: 'FileEnd', text: ''},