diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae031354..b5330130 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,9 +1,9 @@
 cmake_minimum_required( VERSION 3.5 FATAL_ERROR )
 project (urdfdom CXX C)
 
-set (URDF_MAJOR_VERSION 3)
+set (URDF_MAJOR_VERSION 4)
 set (URDF_MINOR_VERSION 0)
-set (URDF_PATCH_VERSION 2)
+set (URDF_PATCH_VERSION 0)
 
 set (URDF_VERSION ${URDF_MAJOR_VERSION}.${URDF_MINOR_VERSION}.${URDF_PATCH_VERSION})
 set (URDF_MAJOR_MINOR_VERSION ${URDF_MAJOR_VERSION}.${URDF_MINOR_VERSION})
diff --git a/package.xml b/package.xml
index e34b5333..e2455b46 100644
--- a/package.xml
+++ b/package.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <package format="2">
   <name>urdfdom</name>
-  <version>3.1.1</version>
+  <version>4.0.0</version>
   <description>A library to access URDFs using the DOM model.</description>
 
   <maintainer email="clalancette@openrobotics.org">Chris Lalancette</maintainer>
@@ -20,7 +20,7 @@
   <build_depend>tinyxml2</build_depend>
   <build_depend>tinyxml2_vendor</build_depend>
   <build_depend version_gte="0.2.3">urdfdom_headers</build_depend>
-  
+
   <buildtool_depend>cmake</buildtool_depend>
 
   <exec_depend>console_bridge_vendor</exec_depend>
@@ -30,7 +30,7 @@
   <exec_depend version_gte="0.2.3">urdfdom_headers</exec_depend>
 
   <test_depend>python3</test_depend>
-  
+
   <export>
     <build_type>cmake</build_type>
   </export>