diff --git a/ChangeLog b/ChangeLog
index 0286b5c7..d3e55fdd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,10 @@
 	  - SPEC file has been removed. (closes #105)
 	* Makefile.am:
 	  - The generation rule for README has been improved.
+	[4.0]
+	* 4.0 branch has been started.
+	* README.md:
+	  - Version number added to the 1st line.
 
 2017.09.07 Kentaro Fukuchi <kentaro@fukuchi.org>
 	* *.[ch]:
diff --git a/README.md b/README.md
index bfd36ab1..7043a189 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
-# libqrencode - QR Code encoding library [![Build Status](https://travis-ci.org/fukuchi/libqrencode.png?branch=master)](https://travis-ci.org/fukuchi/libqrencode)
+# libqrencode 4.0.0 - QR Code encoding library [![Build Status](https://travis-ci.org/fukuchi/libqrencode.png?branch=master)](https://travis-ci.org/fukuchi/libqrencode)
 
-**Attention:** This repository contains the development version of libqrencode. See <https://fukuchi.org/works/qrencode/> for the official stable releases. At this moment, the latest stable release is version 3.4.4, and upcoming version is 4.0.0.
+**Attention:** This repository contains the development version of libqrencode. See <https://fukuchi.org/works/qrencode/> for the official stable releases. At this moment, the latest stable release is version 4.0.0.
 
 GENERAL INFORMATION
 ===================