diff --git a/CMakeLists.txt b/CMakeLists.txt
index 57a1c2e..8b175e5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,7 @@ if(NOT CMAKE_BUILD_TYPE)
 endif(NOT CMAKE_BUILD_TYPE)
 set(CMAKE_BUILD_TYPE ${CMAKE_BUILD_TYPE} CACHE STRING "")
 
-list(APPEND CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake/Modules)
+list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/Modules)
 
 if(NOT LIB_INSTALL_DIR)
    set(LIB_INSTALL_DIR lib)
@@ -80,7 +80,7 @@ endif()
 # Setup the include and linker paths
 ########################################################################
 include_directories(
-    ${CMAKE_SOURCE_DIR}/include
+    ${PROJECT_SOURCE_DIR}/include
     ${LIBUSB_INCLUDE_DIR}
     ${THREADS_PTHREADS_INCLUDE_DIR}
 )
@@ -96,7 +96,7 @@ include_directories(
 # Create uninstall target
 ########################################################################
 configure_file(
-    ${CMAKE_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in
+    ${PROJECT_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in
     ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake
 @ONLY)