diff --git a/CMakeLists.txt b/CMakeLists.txt
index bc7d8aecd..754279e53 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,8 +9,8 @@ if(NOT DEFINED CMAKE_MACOSX_RPATH)
 endif()
 
 # Set the version number for the library
-set (GTSAM_VERSION_MAJOR 3)
-set (GTSAM_VERSION_MINOR 1)
+set (GTSAM_VERSION_MAJOR 4)
+set (GTSAM_VERSION_MINOR 0)
 set (GTSAM_VERSION_PATCH 0)
 math (EXPR GTSAM_VERSION_NUMERIC "10000 * ${GTSAM_VERSION_MAJOR} + 100 * ${GTSAM_VERSION_MINOR} + ${GTSAM_VERSION_PATCH}")
 set (GTSAM_VERSION_STRING "${GTSAM_VERSION_MAJOR}.${GTSAM_VERSION_MINOR}.${GTSAM_VERSION_PATCH}")