diff --git a/build.xml b/build.xml
index 4836cdd10..e94cd8a12 100644
--- a/build.xml
+++ b/build.xml
@@ -7,7 +7,7 @@
   <property file="checkstyle.buildproperties" />
   <property file="${user.home}/checkstyle.buildproperties" />
 
-  <property name="version" value="5.0" />
+  <property name="version" value="5.1-SNAPSHOT" />
   <property name="ant.jar" value="${ant.home}/lib/ant.jar" />
   <property name="antlr.jar" value="lib/antlr.jar" />
   <property name="velocity.jar" value="lib/velocity-dep-1.4.jar" />
diff --git a/pom.xml b/pom.xml
index 30f7c9f61..b58f7353c 100755
--- a/pom.xml
+++ b/pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>checkstyle</groupId>
   <artifactId>checkstyle</artifactId>
-  <version>5.0</version>
+  <version>5.1-SNAPSHOT</version>
   <packaging>jar</packaging>
   <name>Checkstyle</name>
   <url>http://checkstyle.sourceforge.net/</url>