diff --git a/Source/Makefile.postamble b/Source/Makefile.postamble
index 7b5fb68dd..dde5cfe89 100644
--- a/Source/Makefile.postamble
+++ b/Source/Makefile.postamble
@@ -254,6 +254,12 @@ $(GNUSTEP_OBJ_DIR)/NSGString.o \
 $(GNUSTEP_OBJ_DIR)/NSGCString.o \
 	: propList.h
 
+#
+#	Files that include GSeq.h will need a rebuild if it is changed.
+#
+$(GNUSTEP_OBJ_DIR)/NSString.o \
+	: GSeq.h
+
 #
 #	NSGeometry.m needs a recompile if NSGeometry.h is changed.
 #