diff --git a/src/Bigcommerce/Api/Client.php b/src/Bigcommerce/Api/Client.php
index f01e3152..e871c923 100644
--- a/src/Bigcommerce/Api/Client.php
+++ b/src/Bigcommerce/Api/Client.php
@@ -57,6 +57,58 @@ class Client
      * @var string
      */
     static public $api_path;
+    static private $client_id;
+    static private $store_hash;
+    static private $auth_token;
+    static private $stores_prefix = '/stores/%s/v2';
+    static private $api_url = 'https://api.bigcommerce.com';
+    static private $login_url = 'https://login.bigcommerce.com';
+
+    /**
+     * Configure the API client with the required settings to access
+     * the API for a store.
+     *
+     * Accepts OAuth and (for now!) Basic Auth credentials
+     *
+     * @param array $settings
+     */
+    public static function configure($settings)
+    {
+        if (isset($settings['client_id'])) {
+            self::configureOAuth($settings);
+        } else {
+            self::configureBasicAuth($settings);
+        }
+    }
+
+    /**
+     * Configure the API client with the required OAuth credentials.
+     *
+     * Requires a settings array to be passed in with the following keys:
+     *
+     * - client_id
+     * - auth_token
+     * - store_hash
+     *
+     * @param array $settings
+     * @throws \Exception
+     */
+    public static function configureOAuth($settings)
+    {
+        if (!isset($settings['auth_token'])) {
+            throw new Exception("'auth_token' must be provided");
+        }
+
+        if (!isset($settings['store_hash'])) {
+            throw new Exception("'store_hash' must be provided");
+        }
+
+        self::$client_id = $settings['client_id'];
+        self::$auth_token = $settings['auth_token'];
+        self::$store_hash = $settings['store_hash'];
+        self::$api_path = self::$api_url . sprintf(self::$stores_prefix, self::$store_hash);
+        self::$connection = false;
+    }
 
     /**
      * Configure the API client with the required credentials.
@@ -70,7 +122,7 @@ class Client
      * @param array $settings
      * @throws \Exception
      */
-    public static function configure(array $settings)
+    public static function configureBasicAuth(array $settings)
     {
         if (!isset($settings['store_url'])) {
             throw new Exception("'store_url' must be provided");
@@ -162,7 +214,11 @@ private static function connection()
     {
         if (!self::$connection) {
             self::$connection = new Connection();
-            self::$connection->authenticate(self::$username, self::$api_key);
+            if (self::$client_id) {
+                self::$connection->authenticateOauth(self::$client_id, self::$auth_token);
+            } else {
+                self::$connection->authenticateBasic(self::$username, self::$api_key);
+            }
         }
 
         return self::$connection;
@@ -342,6 +398,21 @@ private static function mapCount($object)
         return $object->count;
     }
 
+    /**
+     * Swaps a temporary access code for a long expiry auth token.
+     *
+     * @param \stdClass $object
+     * @return \stdClass
+     */
+    public static function getAuthToken($object)
+    {
+        $context = array_merge(array('grant_type' => 'authorization_code'), (array)$object);
+        $connection = new Connection();
+        $connection->useUrlEncoded();
+
+        return $connection->post(self::$login_url . '/oauth2/token', $context);
+    }
+
     /**
      * Pings the time endpoint to test the connection to a store.
      *
diff --git a/src/Bigcommerce/Api/Connection.php b/src/Bigcommerce/Api/Connection.php
index 84bdb198..12fb659e 100644
--- a/src/Bigcommerce/Api/Connection.php
+++ b/src/Bigcommerce/Api/Connection.php
@@ -7,6 +7,18 @@
  */
 class Connection
 {
+    /**
+     * XML media type.
+     */
+    const MEDIA_TYPE_XML = 'application/xml';
+    /**
+     * JSON media type.
+     */
+    const MEDIA_TYPE_JSON = 'application/json';
+    /**
+     * Default urlencoded media type.
+     */
+    const MEDIA_TYPE_WWW = 'application/x-www-form-urlencoded';
 
     /**
      * @var resource cURL resource
@@ -60,15 +72,19 @@ class Connection
 
     /**
      * Deal with failed requests if failOnError is not set.
-     * @var string | false
+     * @var string|false
      */
     private $lastError = false;
 
     /**
-     * Determines whether requests and responses should be treated
-     * as XML. Defaults to false (using JSON).
+     * Determines whether the response body should be returned as a raw string.
      */
-    private $useXml = false;
+    private $rawResponse = false;
+
+    /**
+     * Determines the default content type to use with requests and responses.
+     */
+    private $contentType;
 
     /**
      * Initializes the connection object.
@@ -96,7 +112,23 @@ public function __construct()
      */
     public function useXml($option = true)
     {
-        $this->useXml = $option;
+        if ($option) {
+            $this->contentType = self::MEDIA_TYPE_XML;
+            $this->rawResponse = true;
+        }
+    }
+
+    /**
+     * Controls whether requests or responses should be treated
+     * as urlencoded form data.
+     *
+     * @param bool $option the new state of this feature
+     */
+    public function useUrlEncoded($option = true)
+    {
+        if ($option) {
+            $this->contentType = self::MEDIA_TYPE_WWW;
+        }
     }
 
     /**
@@ -125,11 +157,23 @@ public function failOnError($option = true)
      * @param string $username
      * @param string $password
      */
-    public function authenticate($username, $password)
+    public function authenticateBasic($username, $password)
     {
         curl_setopt($this->curl, CURLOPT_USERPWD, "$username:$password");
     }
 
+    /**
+     * Sets Oauth authentication headers
+     *
+     * @param string $clientId
+     * @param string $authToken
+     */
+    public function authenticateOauth($clientId, $authToken)
+    {
+        $this->addHeader('X-Auth-Client', $clientId);
+        $this->addHeader('X-Auth-Token', $authToken);
+    }
+
     /**
      * Set a default timeout for the request. The client will error if the
      * request takes longer than this to respond.
@@ -168,6 +212,9 @@ public function verifyPeer($option = false)
 
     /**
      * Add a custom header to the request.
+     *
+     * @param string $header
+     * @param string $value
      */
     public function addHeader($header, $value)
     {
@@ -176,6 +223,7 @@ public function addHeader($header, $value)
 
     /**
      * Remove a header from the request.
+     *
      * @param string $header
      */
     public function removeHeader($header)
@@ -185,10 +233,12 @@ public function removeHeader($header)
 
     /**
      * Get the MIME type that should be used for this request.
+     *
+     * Defaults to application/json
      */
     private function getContentType()
     {
-        return ($this->useXml) ? 'application/xml' : 'application/json';
+        return ($this->contentType) ? $this->contentType : self::MEDIA_TYPE_JSON;
     }
 
     /**
@@ -197,7 +247,6 @@ private function getContentType()
      */
     private function initializeRequest()
     {
-        $this->isComplete = false;
         $this->responseBody = '';
         $this->responseHeaders = array();
         $this->lastError = false;
@@ -222,7 +271,7 @@ private function handleResponse()
             throw new NetworkError(curl_error($this->curl), curl_errno($this->curl));
         }
 
-        $body = ($this->useXml) ? $this->getBody() : json_decode($this->getBody());
+        $body = ($this->rawResponse) ? $this->getBody() : json_decode($this->getBody());
 
         $status = $this->getStatus();
 
@@ -481,6 +530,8 @@ public function getBody()
     /**
      * Access given header from the response.
      *
+     * @param string $header Header name to retrieve
+     *
      * @return string|void
      */
     public function getHeader($header)