diff --git a/CMakeLists.txt b/CMakeLists.txt
index 73990c4..38424a2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -84,7 +84,7 @@ add_custom_target(uninstall
 install (FILES
 			"${CMAKE_CURRENT_BINARY_DIR}/sigc++config.h"
 		DESTINATION
-			"${CMAKE_INSTALL_PREFIX}/lib/${PROJECT_NAME}-${SIGCXX_API_VERSION}/include")
+			"${CMAKE_INSTALL_PREFIX}/include")
 
 install (FILES 
 			"${CMAKE_CURRENT_BINARY_DIR}/sigc++-${SIGCXX_API_VERSION}.pc"
@@ -102,7 +102,7 @@ add_subdirectory (sigc++)
 
 set (PROJECT_CMAKE_NAME		"${PROJECT_NAME}-3")
 set (VERSION_CONFIG     	"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_CMAKE_NAME}ConfigVersion.cmake")
-set (LIBSIGCXX_INCLUDE_DIR	"${CMAKE_INSTALL_PREFIX}/lib/${PROJECT_NAME}-${SIGCXX_API_VERSION}/include")
+set (LIBSIGCXX_INCLUDE_DIR	"${CMAKE_INSTALL_PREFIX}/include")
 set (PROJECT_CONFIG     	"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_CMAKE_NAME}Config.cmake")
 set (CONFIG_INSTALL_DIR 	"lib/cmake/${PROJECT_CMAKE_NAME}")
 set (TARGETS_EXPORT_NAME    "${PROJECT_CMAKE_NAME}Targets")
diff --git a/sigc++.pc.in b/sigc++.pc.in
index 05de315..171b38d 100644
--- a/sigc++.pc.in
+++ b/sigc++.pc.in
@@ -15,4 +15,4 @@ Description: Typesafe signal and callback system for C++
 Version: @PACKAGE_VERSION@
 URL: https://libsigcplusplus.github.io/libsigcplusplus/
 Libs: -L${libdir} -lsigc-@SIGCXX_API_VERSION@
-Cflags: -I${includedir}/sigc++-@SIGCXX_API_VERSION@ -I${libdir}/sigc++-@SIGCXX_API_VERSION@/include
+Cflags: -I${includedir}
diff --git a/sigc++/CMakeLists.txt b/sigc++/CMakeLists.txt
index 86f1be7..076959b 100644
--- a/sigc++/CMakeLists.txt
+++ b/sigc++/CMakeLists.txt
@@ -29,7 +29,7 @@ set_property (TARGET ${SIGCPP_LIB_NAME} PROPERTY VERSION ${PACKAGE_VERSION})
 set_property(TARGET ${SIGCPP_LIB_NAME}  PROPERTY SOVERSION ${LIBSIGCPP_SOVERSION})
 target_compile_definitions( ${SIGCPP_LIB_NAME} PRIVATE -DSIGC_BUILD )
 
-set (INCLUDE_INSTALL_DIR "include/${PROJECT_NAME}-${SIGCXX_API_VERSION}")
+set (INCLUDE_INSTALL_DIR "include/")
 
 install (
 	DIRECTORY "${PROJECT_SOURCE_DIR}"