--- a/igraph.pc.in
+++ b/igraph.pc.in
@@ -11,3 +11,4 @@
 Libs.private: @PKGCONFIG_LIBS_PRIVATE@
 Requires.private: @PKGCONFIG_REQUIRES_PRIVATE@
 Cflags: -I${includedir}/igraph
+Cflags.private: -DIGRAPH_STATIC=1
