diff --git a/addon/serializers/rest-serializer.js b/addon/serializers/rest-serializer.js
index <HASH>..<HASH> 100644
--- a/addon/serializers/rest-serializer.js
+++ b/addon/serializers/rest-serializer.js
@@ -2,6 +2,7 @@ import ActiveModelSerializer from './active-model-serializer';
 import { camelize, singularize, pluralize } from '../utils/inflector';
 
 export default ActiveModelSerializer.extend({
+  serializeIds: 'always',
 
   keyForModel(type) {
     return camelize(type);
diff --git a/tests/unit/serializers/rest-serializer-test.js b/tests/unit/serializers/rest-serializer-test.js
index <HASH>..<HASH> 100644
--- a/tests/unit/serializers/rest-serializer-test.js
+++ b/tests/unit/serializers/rest-serializer-test.js
@@ -29,3 +29,8 @@ test('it hyphenates camelized words', function(assert) {
     }
   });
 });
+
+test('serializeIds defaults to "always"', function(assert) {
+  let defaultState = new RestSerializer;
+  assert.equal(defaultState.serializeIds, 'always');
+});
RestSerializer should always serialize ids

Override the default Serializer behavior in the RestSerializer to
convert ids in the expected way.