diff --git a/lib/src/redis_service.dart b/lib/src/redis_service.dart
index 40d35b2a..b160974f 100644
--- a/lib/src/redis_service.dart
+++ b/lib/src/redis_service.dart
@@ -4,6 +4,7 @@ import 'package:angel_framework/angel_framework.dart';
 import 'package:resp_client/resp_client.dart';
 import 'package:resp_client/resp_commands.dart';
 
+/// An Angel service that reads and writes JSON within a Redis store.
 class RedisService extends Service<String, Map<String, dynamic>> {
   final RespCommands respCommands;
 
@@ -47,6 +48,14 @@ class RedisService extends Service<String, Map<String, dynamic>> {
     return data;
   }
 
+  @override
+  Future<Map<String, dynamic>> modify(String id, Map<String, dynamic> data,
+      [Map<String, dynamic> params]) async {
+    var input = await read(id);
+    input.addAll(data);
+    return await update(id, input, params);
+  }
+
   @override
   Future<Map<String, dynamic>> update(String id, Map<String, dynamic> data,
       [Map<String, dynamic> params]) async {
diff --git a/test/all_test.dart b/test/all_test.dart
index 795ace67..11e4a8cb 100644
--- a/test/all_test.dart
+++ b/test/all_test.dart
@@ -36,11 +36,19 @@ main() async {
     expect(await service.read(id), input);
   });
 
+  test('modify', () async {
+    var id = 'jamboree${new DateTime.now().millisecondsSinceEpoch}';
+    await service.create({'id': id, 'bar': 'baz', 'yes': 'no'});
+    var output = await service.modify(id, {'bar': 'quux'});
+    expect(output, {'id': id, 'bar': 'quux', 'yes': 'no'});
+    expect(await service.read(id), output);
+  });
+
   test('update', () async {
     var id = 'hoopla${new DateTime.now().millisecondsSinceEpoch}';
     await service.create({'id': id, 'bar': 'baz'});
-    var output = await service.update(id, {'bar': 'quux'});
-    expect(output, {'id': id, 'bar': 'quux'});
+    var output = await service.update(id, {'yes': 'no'});
+    expect(output, {'id': id, 'yes': 'no'});
     expect(await service.read(id), output);
   });