diff --git a/CMakeLists.txt b/CMakeLists.txt
index 010d05b824ffee19291e32f453735c55db36cf0e..0f8177b554a21bf0787c157df280905f2c3a065e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -43,11 +43,11 @@ IF(BUILD_PYTHON_INTERFACE)
   STRING(REGEX REPLACE "-" "_" PY_NAME ${PROJECT_NAME})
   INCLUDE_DIRECTORIES(${PYTHON_INCLUDE_DIRS})
   ADD_REQUIRED_DEPENDENCY("dynamic-graph-python >= 3.0.0")
-  SET(CATKIN_REQUIRED_COMPONENTS ${CATKIN_REQUIRED_COMPONENTS rospy)
-  SET(CATKIN_DEPENDS_LIBRARIES ${CATKIN_DEPENDS_LIBRARIES ros_interpreter)
+  SET(CATKIN_REQUIRED_COMPONENTS ${CATKIN_REQUIRED_COMPONENTS} rospy)
+  SET(CATKIN_DEPENDS_LIBRARIES ${CATKIN_DEPENDS_LIBRARIES} ros_interpreter)
 ENDIF(BUILD_PYTHON_INTERFACE)
 
-find_package(catkin REQUIRED COMPONENTS ${CATKIN_REQUIRED_COMPONENTS)
+find_package(catkin REQUIRED COMPONENTS ${CATKIN_REQUIRED_COMPONENTS})
 find_package(realtime_tools)
 
 set(CXX_DISABLE_WERROR False)