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+# Decision for: Add a C++ style guide
+
+<!--
+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
+-->
+
+Proposal accepted on 2020-10-27
+
+Affirming:
+
+-   [austern](https://github.com/austern)
+-   [chandlerc](https://github.com/chandlerc)
+-   [geoffromer](https://github.com/geoffromer)
+-   [gribozavr](https://github.com/gribozavr)
+-   [josh11b](https://github.com/josh11b)
+-   [noncombatant](https://github.com/noncombatant)
+-   [zygoloid](https://github.com/zygoloid)
+
+Abstaining:
+
+-   [tituswinters](https://github.com/tituswinters)
+
+## Rationale
+
+A common, established style guide will allow us to focus on the more important
+aspects of coding and code review. Once we're familiar with the rules, their
+consistent application will result in a more readable codebase, and rules that
+can largely be automated by clang-format will result in a more efficient
+development process.
+
+This particular ruleset attempts to align with our expected lexical rules for
+the Carbon language (for example, comment syntax and capitalization rules),
+which will also mean that we can use a largely consistent style between the
+aspects of the toolchain implemented in C++ and the aspects implemented in
+Carbon.