diff --git a/src/Client.php b/src/Client.php
index f017981..6746743 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -7,7 +7,7 @@
 /**
  * PHP Client for the Marvel API.
  */
-class Client
+class Client implements ClientInterface
 {
     /**
      * The public api key issued by Marvel.
@@ -72,7 +72,7 @@ final public function __construct(
      * @param string $resource The API resource to search for.
      * @param array  $filters  Array of search criteria to use in request.
      *
-     * @return Response
+     * @return ResponseInterface
      *
      * @throws \InvalidArgumentException Thrown if $resource is empty or not a string.
      */
@@ -97,7 +97,7 @@ final public function search($resource, array $filters = [])
      * @param string  $resource The API resource to search for.
      * @param integer $id       The id of the API resource.
      *
-     * @return Response
+     * @return ResponseInterface
      */
     final public function get($resource, $id)
     {
@@ -118,11 +118,11 @@ final public function get($resource, $id)
     /**
      * Send the given API Request.
      *
-     * @param Request $request The request to send.
+     * @param RequestInterface $request The request to send.
      *
-     * @return Response
+     * @return ResponseInterface
      */
-    final private function send(Request $request)
+    final private function send(RequestInterface $request)
     {
         $response = $this->getFromCache($request);
         if ($response !== null) {
@@ -141,11 +141,11 @@ final private function send(Request $request)
     /**
      * Retrieve the Response for the given Request from cache.
      *
-     * @param Request $request The request to send.
+     * @param RequestInterface $request The request to send.
      *
-     * @return Response|null Returns the cached Response or null if it does not exist.
+     * @return ResponseInterface|null Returns the cached Response or null if it does not exist.
      */
-    final private function getFromCache(Request $request)
+    final private function getFromCache(RequestInterface $request)
     {
         if ($this->cache === null) {
             return null;
diff --git a/src/ClientInterface.php b/src/ClientInterface.php
new file mode 100644
index 0000000..b691a25
--- /dev/null
+++ b/src/ClientInterface.php
@@ -0,0 +1,31 @@
+<?php
+
+namespace Chadicus\Marvel\Api;
+
+/**
+ * PHP Client for the Marvel API.
+ */
+interface ClientInterface
+{
+    /**
+     * Execute a search request against the Marvel API.
+     *
+     * @param string $resource The API resource to search for.
+     * @param array  $filters  Array of search criteria to use in request.
+     *
+     * @return ResponseInterface
+     *
+     * @throws \InvalidArgumentException Thrown if $resource is empty or not a string.
+     */
+    public function search($resource, array $filters = []);
+
+    /**
+     * Execute a GET request against the Marvel API for a single resource.
+     *
+     * @param string  $resource The API resource to search for.
+     * @param integer $id       The id of the API resource.
+     *
+     * @return ResponseInterface
+     */
+    public function get($resource, $id);
+}
diff --git a/src/DataContainer.php b/src/DataContainer.php
index 9e8dfbf..d82018b 100644
--- a/src/DataContainer.php
+++ b/src/DataContainer.php
@@ -4,7 +4,7 @@
 
 use DominionEnterprises\Util;
 
-class DataContainer
+class DataContainer implements DataContainerInterface
 {
     /**
      * The requested offset (number of skipped results) of the call.
diff --git a/src/DataContainerInterface.php b/src/DataContainerInterface.php
new file mode 100644
index 0000000..194f606
--- /dev/null
+++ b/src/DataContainerInterface.php
@@ -0,0 +1,42 @@
+<?php
+
+namespace Chadicus\Marvel\Api;
+
+interface DataContainerInterface
+{
+
+    /**
+     * Returns The requested offset (number of skipped results) of the call.
+     *
+     * @return integer
+     */
+    public function getOffset();
+
+    /**
+     * Returns The requested result limit.
+     *
+     * @return integer
+     */
+    public function getLimit();
+
+    /**
+     * Returns The total number of resources available given the current filter set.
+     *
+     * @return integer
+     */
+    public function getTotal();
+
+    /**
+     * Returns The total number of results returned by this call.
+     *
+     * @return integer
+     */
+    public function getCount();
+
+    /**
+     * Returns The list of creators returned by the call.
+     *
+     * @return EntityInterface[]
+     */
+    public function getResults();
+}
diff --git a/src/DataWrapper.php b/src/DataWrapper.php
index 2672c44..071c665 100644
--- a/src/DataWrapper.php
+++ b/src/DataWrapper.php
@@ -4,7 +4,7 @@
 
 use DominionEnterprises\Util;
 
-class DataWrapper
+class DataWrapper implements DataWrapperInterface
 {
     /**
      * The HTTP status code of the returned result.
diff --git a/src/DataWrapperInterface.php b/src/DataWrapperInterface.php
new file mode 100644
index 0000000..06b379c
--- /dev/null
+++ b/src/DataWrapperInterface.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace Chadicus\Marvel\Api;
+
+interface DataWrapperInterface
+{
+    /**
+     * Returns the HTTP status code of the returned result.
+     *
+     * @return integer
+     */
+    public function getCode();
+
+    /**
+     * Returns A string description of the call status.
+     *
+     * @return string
+     */
+    public function getStatus();
+
+    /**
+     * Returns the copyright notice for the returned result.
+     *
+     * @return string
+     */
+    public function getCopyright();
+
+    /**
+     * Returns the attribution notice for this result
+     *
+     * @return string
+     */
+    public function getAttributionText();
+
+    /**
+     * Returns an HTML representation of the attribution notice for this result.
+     *
+     * @return string
+     */
+    public function getAttributionHTML();
+
+    /**
+     * Returns a digest value of the content returned by the call.
+     *
+     * @return string
+     */
+    public function getEtag();
+
+    /**
+     * Returns the results returned by the call.
+     *
+     * @return DataContainerInterface
+     */
+    public function getData();
+}
diff --git a/src/Request.php b/src/Request.php
index a7e85bb..6029468 100644
--- a/src/Request.php
+++ b/src/Request.php
@@ -7,7 +7,7 @@
 /**
  * Represents a request to the Marvel API.
  */
-class Request
+class Request implements RequestInterface
 {
     /**
      * The url for this request.
@@ -80,7 +80,7 @@ final public function getMethod()
     /**
      * Get the body of this request.
      *
-     * @return string
+     * @return array
      */
     final public function getBody()
     {
diff --git a/src/RequestInterface.php b/src/RequestInterface.php
new file mode 100644
index 0000000..b65b494
--- /dev/null
+++ b/src/RequestInterface.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace Chadicus\Marvel\Api;
+
+/**
+ * Represents a request to the Marvel API.
+ */
+interface RequestInterface
+{
+    /**
+     * Get the url of this request.
+     *
+     * @return string
+     */
+    public function getUrl();
+
+    /**
+     * Get the method of this request.
+     *
+     * @return string
+     */
+    public function getMethod();
+
+    /**
+     * Get the body of this request.
+     *
+     * @return array
+     */
+    public function getBody();
+
+    /**
+     * Get the headers of this request.
+     *
+     * @return array
+     */
+    public function getHeaders();
+}
diff --git a/src/Response.php b/src/Response.php
index 9cd76b7..bbf990a 100644
--- a/src/Response.php
+++ b/src/Response.php
@@ -5,7 +5,7 @@
 /**
  * Represents a response from the Marvel API.
  */
-class Response
+class Response implements ResponseInterface
 {
     /**
      * The http status of the response.
@@ -88,7 +88,7 @@ final public function getHeaders()
     /**
      * Returns the parsed API response.
      *
-     * @return DataWrapper
+     * @return DataWrapperInterface
      */
     final public function getDataWrapper()
     {
diff --git a/src/ResponseInterface.php b/src/ResponseInterface.php
new file mode 100644
index 0000000..4c83a5b
--- /dev/null
+++ b/src/ResponseInterface.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace Chadicus\Marvel\Api;
+
+/**
+ * Represents a response from the Marvel API.
+ */
+interface ResponseInterface
+{
+    /**
+     * Returns the HTTP status code of the response.
+     *
+     * @return integer
+     */
+    public function getHttpCode();
+
+    /**
+     * Returns the response body.
+     *
+     * @return array
+     */
+    public function getBody();
+
+    /**
+     * Returns response headers.
+     *
+     * @return array
+     */
+    public function getHeaders();
+
+    /**
+     * Returns the parsed API response.
+     *
+     * @return DataWrapperInterface
+     */
+    public function getDataWrapper();
+}