diff --git a/index.html b/index.html
index cf8ac74..d68eab9 100644
--- a/index.html
+++ b/index.html
@@ -669,6 +669,35 @@ <h2>
     </section>
   </section>
 
+  <section class="informative">
+    <h1>
+Core Data Model
+    </h1>
+    <p>
+This section outlines the core data model concepts. These are elaborated
+in <a href="#did-documents"></a>.
+    </p>
+
+    <section>
+      <h2>
+Document
+      </h2>
+    </section>
+
+    <section>
+      <h2>
+Keys
+      </h2>
+    </section>
+
+    <section>
+      <h2>
+Services
+      </h2>
+    </section>
+
+  </section>
+
   <section>
     <h1>
 Decentralized Identifiers (DIDs)
@@ -813,7 +842,7 @@ <h2>
 
       <p>
 A DID MUST be persistent and immutable, i.e., bound to an entity once
-and never changed (forever). 
+and never changed (forever).
       </p>
 
       <p>
@@ -822,7 +851,7 @@ <h2>
 to multiple underlying distributed ledgers or networks over time,
 thus maintaining its persistence independent of any particular ledger
 or network. However registering the same identifier on multiple
-ledgers or networks introduces extremely hard entityship and 
+ledgers or networks introduces extremely hard entityship and
 <a href="https://en.wikipedia.org/wiki/List_of_DNS_record_types%23SOA">start-of-authority</a>
 (SOA) problems. It also greatly increases implementation complexity
 for developers.
@@ -853,6 +882,7 @@ <h1>
     </h1>
 
     <p>
+DID Documents are the serialization of the <a href="#core-data-model"></a>.
 If a DID is the index key in a key-value pair, then the DID Document is
 the value to which the index key points. The combination of a DID and
 its associated DID Document forms the root record for a decentralized
@@ -860,63 +890,10 @@ <h1>
     </p>
 
     <p>
-A DID Document MUST be a single JSON object conforming to [[RFC7159]].
-For purposes of this version of the DID specification, the format of
-this JSON object is specified in <a href="https://json-ld.org/">JSON-LD</a>, a format for mapping JSON data into
-the RDF semantic graph model as defined by [[JSON-LD]]. Future versions
-of this specification MAY specify other semantic graph formats for a
-DID Document such as JXD (JSON XDI Data), a serialization format for
-the <a href="http://docs.oasis-open.org/xdi/xdi-core/v1.0/csd01/xdi-core-v1.0-csd01.xml">
-XDI graph model</a>.
-    </p>
-
-    <p>
-The following sections define the properties of this JSON object,
+The following sections define the properties of the DID Document,
 including whether these properties are required or optional.
     </p>
 
-    <section>
-      <h2>
-Context
-      </h2>
-
-      <p>
-JSON objects in JSON-LD format must include a JSON-LD context
-statement. The rules for this statement are:
-      </p>
-
-      <ol start="1">
-        <li>
-A DID Document MUST have exactly one top-level context statement.
-        </li>
-
-        <li>
-The key for this property MUST be <code>@context</code>.
-        </li>
-
-        <li>
-The value of this key MUST be the URL for the generic DID context:
-<code>https://w3id.org/did/v1</code>.
-        </li>
-      </ol>
-
-      <p>
-Example (using an example URL):
-      </p>
-
-      <pre class="example nohighlight">
-{
-  "@context": "https://w3id.org/did/v1"
-}
-</pre>
-      <p>
-DID method specifications MAY define their own JSON-LD contexts.
-However it is NOT RECOMMENDED to define a new context unless
-necessary to properly implement the method. Method-specific contexts
-MUST NOT override the terms defined in the generic DID context.
-      </p>
-    </section>
-
     <section>
       <h2>
 DID Subject
@@ -1758,6 +1735,70 @@ <h2>
     </section>
   </section>
 
+  <section>
+    <h1>
+DID Document Syntax
+    </h1>
+        <p>
+A DID Document MUST be a single JSON object conforming to [[RFC7159]].
+Many of the concepts in this document were introduced by example using the
+JSON-LD syntax, a format for mapping JSON data into the RDF semantic graph model as defined by
+[[!JSON-LD]]. This section formalizes how the data model (described in Sections
+<a href="#data-model"></a> and <a href="#did-documents"></a>) is realized in JSON-LD.
+        </p>
+        <p>
+Although syntactic mappings are provided for JSON-LD only, applications and
+services can use any other data representation syntax, such as JXD (JSON XDI Data, a serialization format for
+the <a href="http://docs.oasis-open.org/xdi/xdi-core/v1.0/csd01/xdi-core-v1.0-csd01.xml">
+XDI graph model</a>), XML, YAML, or CBOR, that is capable of expressing the data model.
+        </p>
+
+    <section>
+      <h2>
+JSON-LD
+      </h2>
+
+      <p>
+JSON objects in JSON-LD format must include a JSON-LD context
+statement.  The
+<a href="https://www.w3.org/TR/json-ld/#the-context">JSON-LD Context</a>
+is described in detail in the [[!JSON-LD]] specification. The rules for this
+statement are:
+      </p>
+
+      <ol start="1">
+        <li>
+A DID Document MUST have exactly one top-level context statement.
+        </li>
+
+        <li>
+The key for this property MUST be <code>@context</code>.
+        </li>
+
+        <li>
+The value of this key MUST be the URL for the generic DID context:
+<code>https://w3id.org/did/v1</code>.
+        </li>
+      </ol>
+
+      <p>
+Example (using an example URL):
+      </p>
+
+      <pre class="example nohighlight">
+{
+  "@context": "https://w3id.org/did/v1"
+}
+</pre>
+      <p>
+DID method specifications MAY define their own JSON-LD contexts.
+However it is NOT RECOMMENDED to define a new context unless
+necessary to properly implement the method. Method-specific contexts
+MUST NOT override the terms defined in the generic DID context.
+      </p>
+    </section>
+  </section>
+
   <section>
     <h1>
 DID Methods