diff --git a/comps.dtd b/comps.dtd
index 92c5ebc1..26bcd697 100644
--- a/comps.dtd
+++ b/comps.dtd
@@ -1,11 +1,14 @@
 <?xml encoding="UTF-8"?>
 
-<!ELEMENT comps (group+,category+)>
+<!ELEMENT comps (group+,environment+,category+,langpacks?)>
 <!ATTLIST comps xmlns CDATA #FIXED ''>
 
 <!ELEMENT group (id,name,description,default,uservisible,langonly?, packagelist)>
 <!ATTLIST group xmlns CDATA #FIXED ''>
 
+<!ELEMENT environment (id,name,description,display_order?,grouplist,optionlist)>
+<!ATTLIST environment xmlns CDATA #FIXED ''>
+
 <!ELEMENT category (id,name,description,display_order?,grouplist)>
 <!ATTLIST category xmlns CDATA #FIXED ''>
 
@@ -41,3 +44,6 @@
 
 <!ELEMENT description (#PCDATA)>
 <!ATTLIST description xmlns CDATA #FIXED ''>
+
+<!ELEMENT optionlist (groupid)+>
+<!ATTLIST optionlist xmlns CDATA #FIXED ''>
diff --git a/comps.rng b/comps.rng
index e9a2cb73..ba924264 100644
--- a/comps.rng
+++ b/comps.rng
@@ -20,6 +20,9 @@
       <oneOrMore>
         <ref name="group"/>
       </oneOrMore>
+      <zeroOrMore>
+        <ref name="environment"/>
+      </zeroOrMore>
       <zeroOrMore>
         <ref name="category"/>
       </zeroOrMore>
@@ -120,6 +123,22 @@
       <ref name="packagename"/>
     </element>
   </define>
+  <define name="environment">
+    <element name="environment">
+      <interleave>
+      <ref name="id"/>
+      <optional>
+        <element name="display_order">
+          <ref name="positiveInteger"/>
+        </element>
+      </optional>
+      <ref name="grouplist"/>
+      <optional>
+        <ref name="optionlist"/>
+      </optional>
+     </interleave>
+    </element>
+  </define>
   <define name="category">
     <element name="category">
       <interleave>
@@ -140,6 +159,13 @@
       </oneOrMore>
     </element>
   </define>
+  <define name="optionlist">
+    <element name="optionlist">
+      <oneOrMore>
+        <ref name="groupid"/>
+      </oneOrMore>
+    </element>
+  </define>
   <define name="groupid">
     <element name="groupid">
       <ref name="string"/>