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+# Abseil in gRPC
+
+This document explains how to use Abseil throughout gRPC. Note that this isn't
+supposed to explain general usage of Abseil.
+
+## The version of Abseil
+
+gRPC intends to use the LTS versions of Abseil only because it simplifies
+dependency management. Abseil is being distributed via package distribution
+systems such as vcpkg and cocoapods. If gRPC depends on the certain version
+that aren't registered, gRPC in that system cannot get the right version of
+Abseil when being built, resulting in a build failure.
+Therefore, gRPC will use the LTS version only, preferably the latest one.
+
+## Libraries that are not ready to use
+
+Most of Abseil libraries are okay to use but there are some exceptions
+because they're not going well yet on some of our test machinaries or
+platforms it supports. The following is a list of targets that are NOT
+ready to use.
+
+- `absl/synchronization:*`: This will be ready from the LTS version in 2021.
+- `absl/random`: [WIP](https://github.com/grpc/grpc/pull/23346).
+- `absl/types:variant`: [WIP](https://github.com/grpc/grpc/pull/22961).
+
+## Implemetation only
+
+You can use Abseil in gRPC Core and gRPC C++. But you cannot use it in
+the public interface of gRPC C++ because i) it doesn't gurantee no breaking
+API changes like gRPC C++ does and ii) it may make users change their build
+system to address Abseil.  
+ 
+\ No newline at end of file