diff --git a/docs/manifest-format.txt b/docs/manifest-format.txt
index da0e69f..211344e 100644
--- a/docs/manifest-format.txt
+++ b/docs/manifest-format.txt
@@ -22,6 +22,7 @@
   <!DOCTYPE manifest [
     <!ELEMENT manifest (remote*,
                         default?,
+                        manifest-server?,
                         remove-project*,
                         project*)>
   
@@ -33,6 +34,9 @@
     <!ELEMENT default (EMPTY)>
     <!ATTLIST default remote   IDREF #IMPLIED>
     <!ATTLIST default revision CDATA #IMPLIED>
+
+    <!ELEMENT manifest-server (EMPTY)>
+    <!ATTLIST url              CDATA #REQUIRED>
   
     <!ELEMENT project (EMPTY)>
     <!ATTLIST project name     CDATA #REQUIRED>
@@ -89,6 +93,27 @@
 revision attribute will use this revision.
 
 
+Element manifest-server
+-----------------------
+
+At most one manifest-server may be specified. The url attribute
+is used to specify the URL of a manifest server, which is an
+XML RPC service that will return a manifest in which each project
+is pegged to a known good revision for the current branch and
+target.
+
+The manifest server should implement:
+
+  GetApprovedManifest(branch, target)
+
+The target to use is defined by environment variables TARGET_PRODUCT
+and TARGET_BUILD_VARIANT. These variables are used to create a string
+of the form $TARGET_PRODUCT-$TARGET_BUILD_VARIANT, e.g. passion-userdebug.
+If one of those variables or both are not present, the program will call
+GetApprovedManifest without the target paramater and the manifest server
+should choose a reasonable default target.
+
+
 Element project
 ---------------