diff --git a/CHANGELOG.md b/CHANGELOG.md
index b9c5d7cc..b45508f6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# 2017-02-04 version 2.1.1
+
+  * Fix unpacker's buffer management bug (#561)
+  * Add boost string_view adaptor (#558)
+  * Remove some warnings (#557, #559)
+  * Improve coding style (#556)
+
 # 2017-01-10 version 2.1.0
 
 ## << breaking changes >>
diff --git a/README.md b/README.md
index 110395da..30d9c87f 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 `msgpack` for C/C++
 ===================
 
-Version 2.1.0 [![Build Status](https://travis-ci.org/msgpack/msgpack-c.svg?branch=master)](https://travis-ci.org/msgpack/msgpack-c) [![Build status](https://ci.appveyor.com/api/projects/status/8kstcgt79qj123mw/branch/master?svg=true)](https://ci.appveyor.com/project/redboltz/msgpack-c/branch/master)
+Version 2.1.1 [![Build Status](https://travis-ci.org/msgpack/msgpack-c.svg?branch=master)](https://travis-ci.org/msgpack/msgpack-c) [![Build status](https://ci.appveyor.com/api/projects/status/8kstcgt79qj123mw/branch/master?svg=true)](https://ci.appveyor.com/project/redboltz/msgpack-c/branch/master)
 
 It's like JSON but small and fast.
 
diff --git a/include/msgpack/version_master.h b/include/msgpack/version_master.h
index 6b66c954..d1f50f87 100644
--- a/include/msgpack/version_master.h
+++ b/include/msgpack/version_master.h
@@ -1,3 +1,3 @@
 #define MSGPACK_VERSION_MAJOR    2
 #define MSGPACK_VERSION_MINOR    1
-#define MSGPACK_VERSION_REVISION 0
+#define MSGPACK_VERSION_REVISION 1