diff --git a/configure.ac b/configure.ac
index 6b64110b0..1330d3f27 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1878,10 +1878,13 @@ dnl Set empty BINARY_DIR variable for fltk-config.in (CMake compatibility)
 BINARY_DIR=
 AC_SUBST([BINARY_DIR])
 
+INCLUDE_DIRS="${includedir}"
+AC_SUBST(INCLUDE_DIRS)
+
 dnl Write all of the files...
 AC_CONFIG_HEADERS([config.h:configh.in])
 AC_CONFIG_HEADERS([FL/fl_config.h:fl_config.in])
-AC_CONFIG_FILES([makeinclude fltk.list fltk-config fltk.spec FL/Makefile])
+AC_CONFIG_FILES([makeinclude fltk.list fltk-config fltk.spec FL/Makefile CMake/FLTKConfig.cmake])
 AC_OUTPUT
 
 dnl Make sure the fltk-config script is executable...