diff --git a/lib/models/user.js b/lib/models/user.js
index 531606d4..f13d0be1 100644
--- a/lib/models/user.js
+++ b/lib/models/user.js
@@ -4,10 +4,41 @@
 
 var Model = require('../asteroid').Model;
 
+/**
+ * Default User properties.
+ */
+
+var properties = {
+    id: {type: String, required: true},
+    realm: {type: String},
+    username: {type: String, required: true},
+    // password: {type: String, transient: true}, // Transient property
+    hash: {type: String}, // Hash code calculated from sha256(realm, username, password, salt, macKey)
+    salt: {type: String},
+    macKey: {type: String}, // HMAC to calculate the hash code
+    email: String,
+    emailVerified: Boolean,
+    credentials: [
+        'UserCredential' // User credentials, private or public, such as private/public keys, Kerberos tickets, oAuth tokens, facebook, google, github ids
+    ],
+    challenges: [
+        'Challenge' // Security questions/answers
+    ],
+    // https://en.wikipedia.org/wiki/Multi-factor_authentication
+    /*
+    factors: [
+        'AuthenticationFactor'
+    ],
+    */
+    status: String,
+    created: Date,
+    lastUpdated: Date
+}
+
 
 /**
  * Extends from the built in `asteroid.Model` type.
  */
 
-var User = module.exports = Model.extend('user');
+var User = module.exports = Model.extend('user', properties);