diff --git a/CMakeLists.txt b/CMakeLists.txt
index c54d5a5b16b4bf3f690184af47ba7b3688be0e56..c2b8da5678c440ac81df93f7fc94db480367a521 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -28,8 +28,11 @@ option(DD4HEP_USE_XERCESC "Enable 'Detector Builders' based on XercesC" OFF)
 option(DD4HEP_USE_PYROOT "Enable 'Detector Builders' based on PyROOT" OFF)  # does not work (compile error)
 option(DD4HEP_WITH_GEANT4 "Enable the simulation part based on Geant4" OFF)
 
-#option(DD4HEP_WITH_LCIO  "Build ILD examples with LCIO - builds LCIO as external project or uses pre-installed" ON)
 
+#---------------------------------------------------------------------------------------
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+  set (CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "One of: None Debug Release RelWithDebInfo MinSizeRel." FORCE)
+endif()
 
 #---DD4hep functions and macros -------------------------------------------------------
 include(DD4hep)
diff --git a/cmake/DD4hepConfig.cmake.in b/cmake/DD4hepConfig.cmake.in
index b35ee75ce133d9b8b8a6055c7650d85ba1a8b401..c62538dc877753e34243a2a49a5b82cc0f3b72e8 100644
--- a/cmake/DD4hepConfig.cmake.in
+++ b/cmake/DD4hepConfig.cmake.in
@@ -28,7 +28,10 @@ FIND_PATH( DD4hep_INCLUDE_DIRS
 	NO_DEFAULT_PATH
 )
 
-
+# ---------- default build type  --------------------------------------------------------
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+  set (CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "One of: None Debug Release RelWithDebInfo MinSizeRel." FORCE)
+endif()
 
 # ---------- libraries --------------------------------------------------------
 # do not store find results in cache