diff --git a/composer.lock b/composer.lock
index b791bea..df41f75 100644
--- a/composer.lock
+++ b/composer.lock
@@ -1,10 +1,9 @@
 {
     "_readme": [
         "This file locks the dependencies of your project to a known state",
-        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "hash": "cccae7288cea192fb59b802d3d3baa90",
     "content-hash": "d610fd5ac9bd315dfe12dc4d291d2717",
     "packages": [
         {
@@ -67,7 +66,7 @@
                 "rest",
                 "web service"
             ],
-            "time": "2016-10-08 15:01:37"
+            "time": "2016-10-08T15:01:37+00:00"
         },
         {
             "name": "guzzlehttp/promises",
@@ -118,7 +117,7 @@
             "keywords": [
                 "promise"
             ],
-            "time": "2016-05-18 16:56:05"
+            "time": "2016-05-18T16:56:05+00:00"
         },
         {
             "name": "guzzlehttp/psr7",
@@ -176,7 +175,7 @@
                 "stream",
                 "uri"
             ],
-            "time": "2016-06-24 23:00:38"
+            "time": "2016-06-24T23:00:38+00:00"
         },
         {
             "name": "psr/http-message",
@@ -226,7 +225,7 @@
                 "request",
                 "response"
             ],
-            "time": "2016-08-06 14:39:51"
+            "time": "2016-08-06T14:39:51+00:00"
         }
     ],
     "packages-dev": [
@@ -282,7 +281,7 @@
                 "constructor",
                 "instantiate"
             ],
-            "time": "2015-06-14 21:17:01"
+            "time": "2015-06-14T21:17:01+00:00"
         },
         {
             "name": "hamcrest/hamcrest-php",
@@ -327,7 +326,7 @@
             "keywords": [
                 "test"
             ],
-            "time": "2015-05-11 14:41:42"
+            "time": "2015-05-11T14:41:42+00:00"
         },
         {
             "name": "mockery/mockery",
@@ -392,7 +391,7 @@
                 "test double",
                 "testing"
             ],
-            "time": "2016-05-22 21:52:33"
+            "time": "2016-05-22T21:52:33+00:00"
         },
         {
             "name": "myclabs/deep-copy",
@@ -434,7 +433,7 @@
                 "object",
                 "object graph"
             ],
-            "time": "2016-09-16 13:37:59"
+            "time": "2016-09-16T13:37:59+00:00"
         },
         {
             "name": "phpdocumentor/reflection-common",
@@ -488,7 +487,7 @@
                 "reflection",
                 "static analysis"
             ],
-            "time": "2015-12-27 11:43:31"
+            "time": "2015-12-27T11:43:31+00:00"
         },
         {
             "name": "phpdocumentor/reflection-docblock",
@@ -533,7 +532,7 @@
                 }
             ],
             "description": "With this component, a library can provide support for annotations via DocBlocks or otherwise retrieve information that is embedded in a DocBlock.",
-            "time": "2016-09-30 07:12:33"
+            "time": "2016-09-30T07:12:33+00:00"
         },
         {
             "name": "phpdocumentor/type-resolver",
@@ -580,7 +579,7 @@
                     "email": "me@mikevanriel.com"
                 }
             ],
-            "time": "2016-06-10 07:14:17"
+            "time": "2016-06-10T07:14:17+00:00"
         },
         {
             "name": "phpspec/prophecy",
@@ -642,7 +641,7 @@
                 "spy",
                 "stub"
             ],
-            "time": "2016-06-07 08:13:47"
+            "time": "2016-06-07T08:13:47+00:00"
         },
         {
             "name": "phpunit/php-code-coverage",
@@ -705,7 +704,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2016-07-26 14:39:29"
+            "time": "2016-07-26T14:39:29+00:00"
         },
         {
             "name": "phpunit/php-file-iterator",
@@ -752,7 +751,7 @@
                 "filesystem",
                 "iterator"
             ],
-            "time": "2015-06-21 13:08:43"
+            "time": "2015-06-21T13:08:43+00:00"
         },
         {
             "name": "phpunit/php-text-template",
@@ -793,7 +792,7 @@
             "keywords": [
                 "template"
             ],
-            "time": "2015-06-21 13:50:34"
+            "time": "2015-06-21T13:50:34+00:00"
         },
         {
             "name": "phpunit/php-timer",
@@ -837,7 +836,7 @@
             "keywords": [
                 "timer"
             ],
-            "time": "2016-05-12 18:03:57"
+            "time": "2016-05-12T18:03:57+00:00"
         },
         {
             "name": "phpunit/php-token-stream",
@@ -886,7 +885,7 @@
             "keywords": [
                 "tokenizer"
             ],
-            "time": "2015-09-15 10:49:45"
+            "time": "2015-09-15T10:49:45+00:00"
         },
         {
             "name": "phpunit/phpunit",
@@ -968,7 +967,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2016-10-07 13:03:26"
+            "time": "2016-10-07T13:03:26+00:00"
         },
         {
             "name": "phpunit/phpunit-mock-objects",
@@ -1027,7 +1026,7 @@
                 "mock",
                 "xunit"
             ],
-            "time": "2016-10-09 07:01:45"
+            "time": "2016-10-09T07:01:45+00:00"
         },
         {
             "name": "sebastian/code-unit-reverse-lookup",
@@ -1072,26 +1071,26 @@
             ],
             "description": "Looks up which function or method a line of code belongs to",
             "homepage": "https://github.com/sebastianbergmann/code-unit-reverse-lookup/",
-            "time": "2016-02-13 06:45:14"
+            "time": "2016-02-13T06:45:14+00:00"
         },
         {
             "name": "sebastian/comparator",
-            "version": "1.2.0",
+            "version": "1.2.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/comparator.git",
-                "reference": "937efb279bd37a375bcadf584dec0726f84dbf22"
+                "reference": "2b7424b55f5047b47ac6e5ccb20b2aea4011d9be"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/comparator/zipball/937efb279bd37a375bcadf584dec0726f84dbf22",
-                "reference": "937efb279bd37a375bcadf584dec0726f84dbf22",
+                "url": "https://api.github.com/repos/sebastianbergmann/comparator/zipball/2b7424b55f5047b47ac6e5ccb20b2aea4011d9be",
+                "reference": "2b7424b55f5047b47ac6e5ccb20b2aea4011d9be",
                 "shasum": ""
             },
             "require": {
                 "php": ">=5.3.3",
                 "sebastian/diff": "~1.2",
-                "sebastian/exporter": "~1.2"
+                "sebastian/exporter": "~1.2 || ~2.0"
             },
             "require-dev": {
                 "phpunit/phpunit": "~4.4"
@@ -1136,7 +1135,7 @@
                 "compare",
                 "equality"
             ],
-            "time": "2015-07-26 15:48:44"
+            "time": "2017-01-29T09:50:25+00:00"
         },
         {
             "name": "sebastian/diff",
@@ -1188,7 +1187,7 @@
             "keywords": [
                 "diff"
             ],
-            "time": "2015-12-08 07:14:41"
+            "time": "2015-12-08T07:14:41+00:00"
         },
         {
             "name": "sebastian/environment",
@@ -1238,7 +1237,7 @@
                 "environment",
                 "hhvm"
             ],
-            "time": "2016-08-18 05:49:44"
+            "time": "2016-08-18T05:49:44+00:00"
         },
         {
             "name": "sebastian/exporter",
@@ -1305,7 +1304,7 @@
                 "export",
                 "exporter"
             ],
-            "time": "2016-06-17 09:04:28"
+            "time": "2016-06-17T09:04:28+00:00"
         },
         {
             "name": "sebastian/global-state",
@@ -1356,7 +1355,7 @@
             "keywords": [
                 "global state"
             ],
-            "time": "2015-10-12 03:26:01"
+            "time": "2015-10-12T03:26:01+00:00"
         },
         {
             "name": "sebastian/object-enumerator",
@@ -1402,7 +1401,7 @@
             ],
             "description": "Traverses array structures and object graphs to enumerate all referenced objects",
             "homepage": "https://github.com/sebastianbergmann/object-enumerator/",
-            "time": "2016-01-28 13:25:10"
+            "time": "2016-01-28T13:25:10+00:00"
         },
         {
             "name": "sebastian/recursion-context",
@@ -1455,7 +1454,7 @@
             ],
             "description": "Provides functionality to recursively process PHP variables",
             "homepage": "http://www.github.com/sebastianbergmann/recursion-context",
-            "time": "2015-11-11 19:50:13"
+            "time": "2015-11-11T19:50:13+00:00"
         },
         {
             "name": "sebastian/resource-operations",
@@ -1497,7 +1496,7 @@
             ],
             "description": "Provides a list of PHP built-in functions that operate on resources",
             "homepage": "https://www.github.com/sebastianbergmann/resource-operations",
-            "time": "2015-07-28 20:34:47"
+            "time": "2015-07-28T20:34:47+00:00"
         },
         {
             "name": "sebastian/version",
@@ -1540,7 +1539,7 @@
             ],
             "description": "Library that helps with managing the version number of Git-hosted PHP projects",
             "homepage": "https://github.com/sebastianbergmann/version",
-            "time": "2016-02-04 12:56:52"
+            "time": "2016-02-04T12:56:52+00:00"
         },
         {
             "name": "symfony/yaml",
@@ -1589,7 +1588,7 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "time": "2016-09-25 08:27:07"
+            "time": "2016-09-25T08:27:07+00:00"
         },
         {
             "name": "webmozart/assert",
@@ -1639,7 +1638,7 @@
                 "check",
                 "validate"
             ],
-            "time": "2016-08-09 15:02:57"
+            "time": "2016-08-09T15:02:57+00:00"
         }
     ],
     "aliases": [],
diff --git a/src/Response.php b/src/Response.php
index b5d158d..8843fb2 100644
--- a/src/Response.php
+++ b/src/Response.php
@@ -98,9 +98,9 @@ public function __set($name, $value)
      */
     public function __isset($name)
     {
-        return $this->data->{$name};
+        return isset($this->data->{$name});
     }
-    
+
     /**
      * @param $name
      */
diff --git a/tests/ResponseTest.php b/tests/ResponseTest.php
index de991be..44e4e10 100644
--- a/tests/ResponseTest.php
+++ b/tests/ResponseTest.php
@@ -117,4 +117,16 @@ public function testIssetReturnsCorrectly()
         static::assertTrue(isset($response->One->translations[0]->code));
         static::assertNotTrue(isset($response->Two->translations[0]->code));
     }
-}
\ No newline at end of file
+
+    public function testIssetReturnsCorrectlyWithMissingField()
+    {
+        $data = '{"data":{"One":1}}';
+
+        $jsonObj = json_decode($data);
+
+        $response = new Response($jsonObj);
+
+        static::assertTrue(isset($response->One));
+        static::assertNotTrue(isset($response->Two));
+    }
+}