diff --git a/test_constraints/CMakeLists.txt b/test_constraints/CMakeLists.txt
index 6b4693d5..aec592e4 100644
--- a/test_constraints/CMakeLists.txt
+++ b/test_constraints/CMakeLists.txt
@@ -1,4 +1,4 @@
-include_directories(${CMAKE_BINARY_DIR}/tests)
+include_directories(${CMAKE_SOURCE_DIR}/tests)
 
 add_custom_target(test_sqlpp_constraints COMMAND true)