diff --git a/README.md b/README.md
index 294b864..199b0f2 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,32 @@
-# whmcs-sdk
-A simple PHP wrapper for WHMCS's API
+# WHMCS SDK
+
+A simple wrapper around the WHMCS SDK.
+
+## Installation
+This package is installed using Composer. You can use the following command to add it to a project.
+
+```bash
+composer require hansadema/whmcs-sdk
+composer update
+```
+
+## Usage
+Create an API client:
+```php
+$api = new \HansAdema\WhmcsSdk\Client('https://example.com/whmcs/installation/url/', 'myusername', 'mypassword');
+```
+
+Send an API request:
+```php
+try {
+    $result = $api->acceptOrder([
+        'orderid' => 123,
+        'serverid' => 456,
+        //...
+    ]);
+} catch (\HansAdema\WhmcsSdk\RequestException $e) {
+    echo "Error connecting to WHMCS: ".$e->getMessage();
+} catch (\HansAdema\WhmcsSdk\ResponseException $e) {
+    echo "There was an issue with your API call: ".$e->getMessage();
+}
+```
\ No newline at end of file
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..13a4c6e
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,20 @@
+{
+  "name": "HansAdema/whmcs-sdk",
+  "description": "Simple OOP wrapper for the WHMCS API",
+  "minimum-stability": "stable",
+  "license": "MIT",
+  "authors": [
+    {
+      "name": "Hans Adema",
+      "email": "hans@hansadema.nl"
+    }
+  ],
+  "autoload": {
+    "psr-4": {
+      "HansAdema\\WhmcsSdk\\" : "src/"
+    }
+  },
+  "require": {
+    "guzzlehttp/guzzle": "~6.0"
+  }
+}
\ No newline at end of file
diff --git a/composer.lock b/composer.lock
new file mode 100644
index 0000000..b0d022d
--- /dev/null
+++ b/composer.lock
@@ -0,0 +1,247 @@
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+        "This file is @generated automatically"
+    ],
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+                ],
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+            "license": [
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+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
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+                    "src/functions_include.php"
+                ]
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+            "license": [
+                "MIT"
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+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
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+                },
+                "files": [
+                    "src/functions_include.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
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+                    "name": "Michael Dowling",
+                    "email": "mtdowling@gmail.com",
+                    "homepage": "https://github.com/mtdowling"
+                },
+                {
+                    "name": "Tobias Schultze",
+                    "homepage": "https://github.com/Tobion"
+                }
+            ],
+            "description": "PSR-7 message implementation that also provides common utility methods",
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+        },
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+                "url": "https://github.com/php-fig/http-message.git",
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+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
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+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "http://www.php-fig.org/"
+                }
+            ],
+            "description": "Common interface for HTTP messages",
+            "homepage": "https://github.com/php-fig/http-message",
+            "keywords": [
+                "http",
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+            ],
+            "time": "2016-08-06 14:39:51"
+        }
+    ],
+    "packages-dev": [],
+    "aliases": [],
+    "minimum-stability": "stable",
+    "stability-flags": [],
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+    "prefer-lowest": false,
+    "platform": [],
+    "platform-dev": []
+}
diff --git a/src/Client.php b/src/Client.php
new file mode 100644
index 0000000..0e27c80
--- /dev/null
+++ b/src/Client.php
@@ -0,0 +1,93 @@
+<?php
+
+namespace HansAdema\WhmcsSdk;
+
+use GuzzleHttp\Client as Guzzle;
+use GuzzleHttp\Exception\ClientException;
+use HansAdema\WhmcsSdk\Exceptions\Exception;
+use HansAdema\WhmcsSdk\Exceptions\RequestException;
+use HansAdema\WhmcsSdk\Exceptions\ResponseException;
+
+class Client
+{
+    /**
+     * @var Guzzle
+     */
+    protected $http;
+
+    /**
+     * @var string The WHMCS API username
+     */
+    protected $username;
+
+    /**
+     * @var string The WHMCS API password
+     */
+    protected $password;
+
+    /**
+     * @var string The WHMCS installation url
+     */
+    protected $url;
+
+    /**
+     * Api constructor.
+     * @param string $url The WHMCS installation URL
+     * @param string $username The WHMCS API username
+     * @param string $password The WHMCS API password
+     */
+    public function __construct($url, $username, $password)
+    {
+        $this->url = $url;
+        $this->username = $username;
+        $this->password = md5($password);
+
+        $this->http = new Guzzle(['base_uri' => $url . 'includes/api.php']);
+    }
+
+    /**
+     * Send a request to WHMCS
+     *
+     * @param string $action The API action name
+     * @param array $params The action parameters
+     * @return array The API response data
+     * @throws Exception
+     */
+    public function sendRequest($action, $params = [])
+    {
+        try {
+            $response = $this->http->post('', [
+                'form_params' => array_merge($params, [
+                    'username' => $this->username,
+                    'password' => $this->password,
+                    'action' => $action,
+                    'responsetype' => 'json',
+                ]),
+            ]);
+        } catch (ClientException $e) {
+            throw new RequestException($e->getResponse());
+        }
+
+        $data = json_decode($response->getBody(), true);
+
+        if (isset($data['result']) && $data['result'] === 'success') {
+            return $data;
+        } else {
+            throw new ResponseException($response);
+        }
+    }
+
+    /**
+     * Magic method to automagically build a sendRequest
+     *
+     * @param string $name
+     * @param array $arguments
+     * @return array
+     */
+    public function __call($name, $arguments)
+    {
+        $params = isset($arguments[0]) && is_array($arguments[0]) ? $arguments[0] : [];
+
+        return $this->sendRequest(ucfirst($name), $params);
+    }
+}
\ No newline at end of file
diff --git a/src/Exceptions/Exception.php b/src/Exceptions/Exception.php
new file mode 100644
index 0000000..a23b541
--- /dev/null
+++ b/src/Exceptions/Exception.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace HansAdema\WhmcsSdk\Exceptions;
+
+use Psr\Http\Message\ResponseInterface;
+
+class Exception extends \Exception
+{
+    /**
+     * @var ResponseInterface
+     */
+    protected $response;
+
+    /**
+     * Build a new exception
+     *
+     * @param ResponseInterface $response
+     */
+    public function __construct($response)
+    {
+        $data = json_decode($response->getBody(), true);
+
+        parent::__construct($data['message'], $response->getStatusCode());
+
+        $this->response = $response;
+    }
+
+    /**
+     * @return ResponseInterface
+     */
+    public function getResponse()
+    {
+        return $this->response;
+    }
+}
\ No newline at end of file
diff --git a/src/Exceptions/RequestException.php b/src/Exceptions/RequestException.php
new file mode 100644
index 0000000..9f5dc82
--- /dev/null
+++ b/src/Exceptions/RequestException.php
@@ -0,0 +1,15 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: hans
+ * Date: 15-2-17
+ * Time: 22:12
+ */
+
+namespace HansAdema\WhmcsSdk\Exceptions;
+
+
+class RequestException extends Exception
+{
+
+}
\ No newline at end of file
diff --git a/src/Exceptions/ResponseException.php b/src/Exceptions/ResponseException.php
new file mode 100644
index 0000000..f8a2364
--- /dev/null
+++ b/src/Exceptions/ResponseException.php
@@ -0,0 +1,15 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: hans
+ * Date: 15-2-17
+ * Time: 22:12
+ */
+
+namespace HansAdema\WhmcsSdk\Exceptions;
+
+
+class ResponseException extends Exception
+{
+
+}
\ No newline at end of file