diff --git a/schemas/adl-0.dtd b/schemas/adl-0.dtd
index 5e59048..a81ffef 100755
--- a/schemas/adl-0.dtd
+++ b/schemas/adl-0.dtd
@@ -13,7 +13,7 @@
     <!--  ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::  -->
     
     <!--
-        $Revision: 1.2 $
+        $Revision: 1.3 $
  	    -->
 
 <!--  ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::  -->
@@ -47,7 +47,7 @@
 <!ENTITY % Permissions "none|read|insert|noedit|edit|all" >
 
 <!-- 
-	data types which can be used in a definition to provide validation - 
+	data types which can be used in a typedef to provide validation - 
 	e.g. a string can be used with a regexp or a scalar can be used with 
 	min and max values 
 	string: 		  varchar		java.sql.Types.VARCHAR
@@ -76,7 +76,7 @@
   list :      a list of some other entity that links to me (i.e. the 'one' end of
               a one-to-many link);
 	link : 			a many to many link (via a link table);
-	defined : 	a type defined by a definition.
+	defined : 	a type defined by a typedef.
 -->
 <!ENTITY % ComplexDataTypes "entity|link|list|defined" >
 
@@ -109,13 +109,22 @@
 <!--  Elements																	                                -->
 <!--  ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::  -->
 
-<!-- the application that the document describes: required top level element -->
-<!ELEMENT application ( documentation?, content?, definition*,  group*, entity*)>
+<!-- 
+  the application that the document describes: required top level element
+  
+  name:     the name of this application
+  version:  the version number of this application
+  assembly: C# implementation detail, should not be here
+  namespace:  C# implementation detail, should not be here
+-->
+<!ELEMENT application ( documentation?, content?, type*, typedef*,  group*, entity*)>
 <!ATTLIST application 
 	name 		  CDATA 						#REQUIRED
+  assembly  CDATA             #IMPLIED
+  namespace CDATA             #IMPLIED
 	version 	CDATA 						#IMPLIED>
 
-    <!-- 
+<!-- 
 	the definition of a defined type. At this stage a defined type is either
 	a string		in which case it must have size and pattern, or
 	a scalar		in which case it must have minimum and/or maximum
@@ -124,16 +133,16 @@
 	Validation may be done client-side and/or server-side at application layer
 	and/or server side at database layer.
 
-  name:     the name of this definition
+  name:     the name of this typedef
   type:     the simple type on which this defined type is based
   size:     the data size of this defined type
   pattern:  a regular expression which values for this type must match
   minimum:  the minimum value for this type (if base type is scalar)
   maximum:  the maximum value for this type (if base type is scalar)
   -->
-    <!ELEMENT definition (documentation?, help*) >
+<!ELEMENT typedef (documentation?, in-implementation*, help*) >
 
-<!ATTLIST definition 
+<!ATTLIST typedef 
 	name 		  CDATA 						#REQUIRED
 	type 		  (%DefinableDataTypes;) 		#REQUIRED
 	size 		  CDATA 						#IMPLIED
@@ -141,7 +150,19 @@
 	minimum 	CDATA 						#IMPLIED
 	maximum 	CDATA 						#IMPLIED>
 
+<!--
+  information about how to translate a type into types known to different target
+  languages. TODO: Once again I'm not wholly comfortable with the name; I'm not 
+  really comfortable that this belongs in ADL at all.
+  
+  target:     the target language
+  value:      the type to use in that target language
+-->
+<!ELEMENT in-implementation (documentation?)>
 
+<!ATTLIST in-implementation
+      target  CDATA           #REQUIRED
+      value   CDATA           #REQUIRED>
 
 <!-- 
   a group of people with similar permissions to one another 
@@ -165,12 +186,17 @@
   natural-key:  if present, the name of a property of this entity which forms
                 a natural primary key [NOTE: Only partly implemented. NOTE: much of
                 the present implementation assumes all primary keys will be 
-                integers. This needs to be fixed!]
+                integers. This needs to be fixed!] TODO: remove; replace with the
+                'key' element, below.
+  table:        the name of the table in which this entity is stored. TODO: more thought
 -->
-<!ELEMENT entity ( documentation?, content?, property*, permission*, (form | page | list)*)>
+<!ELEMENT entity ( documentation?, content?, 
+      (property | key | one-to-many | many-to-many | many-to-one)*,
+      permission*, (form | page | list)*)>
 <!ATTLIST entity 
     name      CDATA           #REQUIRED
-    natural-key CDATA         #IMPLIED>
+    natural-key CDATA         #IMPLIED
+    table     CDATA           #IMPLIED>
 
 <!-- 
   contains documentation on the element which immediately contains it. TODO:
@@ -179,6 +205,11 @@
 -->
 <!ELEMENT documentation (#PCDATA)>
 
+
+<!-- an explicit primary key, possibly compound -->
+<!ELEMENT key (property*)>
+
+
 <!-- 
 	a property (field) of an entity (table) 
 	
@@ -186,7 +217,7 @@
 	type:			  the type of this property.
 	default:		the default value of this property. There will probably be 
 					    magic values of this!
-	definition:	name of the definition to use, it type = 'defined'.
+	typedef:	  name of the typedef to use, it type = 'defined'.
 	distinct:		distinct='system' required that every value in the system 
 					    will be distinct (i.e. natural primary key);
 					    distinct='user' implies that the value may be used by users 
@@ -205,6 +236,13 @@
   concrete:   if set to 'false', this property is not stored in the 
               database but must be computed (manually written code must
               be provided to support this)
+              
+  column:     name of the column in a SQL database table in which this property
+              is stored. TODO: Think about this.
+  unsaved-value:
+              of a property whose persistent value is set on first being 
+              committed to persistent store, the value which it holds before
+              it has been committed
 -->
 <!ELEMENT property ( documentation?, permission*, option*, prompt*, help*, ifmissing*)>
 
@@ -212,13 +250,15 @@
 	name 		    CDATA 					#REQUIRED
 	type 		    (%AllDataTypes;)  #REQUIRED
 	default 	  CDATA 					#IMPLIED
-	definition 	CDATA 					#IMPLIED
+	typedef 	CDATA 					#IMPLIED
 	distinct 	  (none|all|user|system) 	#IMPLIED
 	entity 		  CDATA 					#IMPLIED
   farkey      CDATA           #IMPLIED
  	required 	  %Boolean; 			#IMPLIED
 	size 		    CDATA 					#IMPLIED
-  concrete    %Boolean;       #IMPLIED>
+  concrete    %Boolean;       #IMPLIED
+  column      CDATA           #IMPLIED
+  unsaved-value CDATA         #IMPLIED>
 
 <!-- 
 	one of an explicit list of optional values a property may have 
@@ -272,7 +312,7 @@
 
 <!-- 
 	helptext about a property of an entity, or a field of a page, form or 
-	list, or a definition. Typically there will be only one of these per property
+	list, or a typedef. Typically there will be only one of these per property
   per locale; if there are more than one all those matching the locale may
   be concatenated, or just one may be used.