diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1c4358d..839a423 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@ set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 add_library(eternal INTERFACE)
-target_include_directories(eternal SYSTEM INTERFACE ${CMAKE_SOURCE_DIR}/include)
+target_include_directories(eternal SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/include)
 
 option(WITH_TESTS "Enable tests" ON)
 if (WITH_TESTS)