diff --git a/executable_semantics/interpreter/interpreter.h b/executable_semantics/interpreter/interpreter.h
index 49c813c7e3c1..c8c1190451f9 100644
--- a/executable_semantics/interpreter/interpreter.h
+++ b/executable_semantics/interpreter/interpreter.h
@@ -31,7 +31,7 @@ extern State* state;
 
 void InitEnv(const Declaration& d, Env* env);
 void PrintStack(const Stack<Frame*>& ls, llvm::raw_ostream& out);
-void PrintEnv(Env values);
+void PrintEnv(Env values, llvm::raw_ostream& out);
 
 /***** Interpreters *****/
 
diff --git a/executable_semantics/interpreter/typecheck.cpp b/executable_semantics/interpreter/typecheck.cpp
index ed3a9ebbe2cb..85a884e9e7b2 100644
--- a/executable_semantics/interpreter/typecheck.cpp
+++ b/executable_semantics/interpreter/typecheck.cpp
@@ -17,6 +17,7 @@
 #include "executable_semantics/common/tracing_flag.h"
 #include "executable_semantics/interpreter/interpreter.h"
 #include "executable_semantics/interpreter/value.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Casting.h"
 
 using llvm::cast;
@@ -24,6 +25,13 @@ using llvm::dyn_cast;
 
 namespace Carbon {
 
+void PrintTypeEnv(TypeEnv types, llvm::raw_ostream& out) {
+  llvm::ListSeparator sep;
+  for (const auto& [name, type] : types) {
+    out << sep << name << ": " << *type;
+  }
+}
+
 static void ExpectType(int line_num, const std::string& context,
                        const Value* expected, const Value* actual) {
   if (!TypeEqual(expected, actual)) {
@@ -259,7 +267,11 @@ static auto Substitute(TypeEnv dict, const Value* type) -> const Value* {
 auto TypeCheckExp(const Expression* e, TypeEnv types, Env values)
     -> TCExpression {
   if (tracing_output) {
-    llvm::outs() << "checking expression " << *e << "\n";
+    llvm::outs() << "checking expression " << *e << "\ntypes: ";
+    PrintTypeEnv(types, llvm::outs());
+    llvm::outs() << "\nvalues: ";
+    PrintEnv(values, llvm::outs());
+    llvm::outs() << "\n";
   }
   switch (e->Tag()) {
     case Expression::Kind::IndexExpression: {
@@ -522,11 +534,15 @@ auto TypeCheckExp(const Expression* e, TypeEnv types, Env values)
 auto TypeCheckPattern(const Pattern* p, TypeEnv types, Env values,
                       const Value* expected) -> TCPattern {
   if (tracing_output) {
-    llvm::outs() << "checking pattern, ";
+    llvm::outs() << "checking pattern " << *p;
     if (expected) {
-      llvm::outs() << "expecting " << *expected;
+      llvm::outs() << ", expecting " << *expected;
     }
-    llvm::outs() << ", " << *p << "\n";
+    llvm::outs() << "\ntypes: ";
+    PrintTypeEnv(types, llvm::outs());
+    llvm::outs() << "\nvalues: ";
+    PrintEnv(values, llvm::outs());
+    llvm::outs() << "\n";
   }
   switch (p->Tag()) {
     case Pattern::Kind::AutoPattern: {