diff --git a/refpolicy/doc/policy.dtd b/refpolicy/doc/policy.dtd
index 166f8279..b415fd4b 100644
--- a/refpolicy/doc/policy.dtd
+++ b/refpolicy/doc/policy.dtd
@@ -4,9 +4,12 @@
 <!ELEMENT layer (summary,module+)>
 <!ATTLIST layer
       name CDATA #REQUIRED>
-<!ELEMENT module (summary,desc?,(interface|template)*)>
+<!ELEMENT module (summary,desc?,required?,(interface|template)*)>
 <!ATTLIST module 
       name CDATA #REQUIRED>
+<!ELEMENT required (#PCDATA)>
+<!ATTLIST required
+      val (true|false) "false">
 <!ELEMENT tunable (#PCDATA)>
 <!ATTLIST tunable
       name CDATA #REQUIRED