diff --git a/components/Makefile b/components/Makefile
index 4962b71..b489841 100644
--- a/components/Makefile
+++ b/components/Makefile
@@ -4,7 +4,7 @@
 # Note that we don't have the concept of a "library of everything" so far.
 #
 
-.PHONY:		all sch catalog clean spotless
+.PHONY:		all sch catalog missing clean spotless
 
 all:		sch
 
@@ -21,6 +21,9 @@ catalog:	DESCR-dcm
 		genex -p -L . EXPAND DESCR-dcm >catalog.pdf || \
 		  { rm -f catalog.pdf; exit 1; }
 
+missing:
+		../scripts/missing-in-tree -L . EXPAND
+
 #loe:
 #		./mkloe