diff --git a/lib/Makefile.ctan b/lib/Makefile.ctan
index c09c5d2..e004e14 100644
--- a/lib/Makefile.ctan
+++ b/lib/Makefile.ctan
@@ -1,4 +1,17 @@
-# make a zip for CTAN submission including the TeX directory structure
+################################################################
+# make a zip for CTAN submission including the TeX directory structure.
+#
+# The overall procedure is to run make in this directory $(HERE) and then
+# export it to a temporary directory $(EXPORTED) without all the generated
+# files. On this directory we run "make ctanext" (see below) which makes a
+# CTAN-compliant directory structure, and zips it up to the file
+# <package>.ctan.zip which can be submitted to the CTAN maintainers.
+#
+# Note that part of the CTAN submission is a zip file with a TDS-compliant
+# directory struture, which is generated by running "make tdsext" (see below)
+# on $(EXPORTED). 
+################################################################
+
 HERE   	        = $(shell pwd)
 TMP    	        = /tmp
 TDSCOLL 	= proposal