diff --git a/README.md b/README.md
index 1750a94..66132f0 100644
--- a/README.md
+++ b/README.md
@@ -47,8 +47,8 @@ For more examples see the [examples directory](examples).
 This project aims to be 100% compatible with [Pusher's features](https://pusher.com/features) in `v1.3`.
 
 - [X] Subscribe to channels
-- [ ] Presence channels
-- [ ] Authentication
+- [x] Presence channels
+- [x] Authentication
 
 # License
 
diff --git a/src/ApiSettings.php b/src/ApiSettings.php
index 544144f..b1179ec 100644
--- a/src/ApiSettings.php
+++ b/src/ApiSettings.php
@@ -31,9 +31,9 @@ public static function getVersion(string $version = ''): string
      * Create WebSocket URL for given App ID.
      *
      * @param  string $appId
-     * @return string
+     * @return array
      */
-    public static function createUrl(string $appId, string $cluster = null): string
+    public static function createUrl(string $appId, string $cluster = null, string $host = null): string
     {
         $query = [
             'client' => 'api-clients/pusher (https://php-api-clients.org/clients/pusher)',
@@ -41,11 +41,13 @@ public static function createUrl(string $appId, string $cluster = null): string
             'version' => ApiSettings::getVersion(),
         ];
 
-        $host = ($cluster !== null) ? "ws-{$cluster}.pusher.com" : 'ws.pusherapp.com';
+        if (!$host) {
+            $host = ($cluster !== null) ? "ws-{$cluster}.pusher.com" : 'ws.pusherapp.com';
+        }
 
         return 'wss://'.$host.'/app/' .
-            $appId .
-            '?' . \http_build_query($query)
-        ;
+               $appId .
+               '?' . \http_build_query($query)
+            ;
     }
 }
diff --git a/src/AsyncClient.php b/src/AsyncClient.php
index 9915d24..1acf4ed 100644
--- a/src/AsyncClient.php
+++ b/src/AsyncClient.php
@@ -6,11 +6,11 @@
 use React\EventLoop\LoopInterface;
 use RuntimeException;
 use Rx\Observable;
-use function Rx\p;
 use Rx\Scheduler;
 use Rx\Subject\Subject;
 use Rx\Websocket\WebsocketErrorException;
 use Throwable;
+use function Rx\p;
 
 final class AsyncClient
 {
@@ -38,19 +38,32 @@ final class AsyncClient
      */
     private $client;
 
+    /**
+     * @var string|null
+     */
+    private $authEndpoint;
+
+    /**
+     * @var array|null
+     */
+    private $authEndpointHeaders;
+
     /**
      * @var Observable
      */
     private $connected;
 
     /**
-     * @internal
-     * @param  Subject                   $client
+     * @param Subject $client
+     *
      * @throws \InvalidArgumentException
+     * @internal
      */
-    public function __construct(Subject $client)
+    public function __construct(Subject $client, string $authEndpoint = null, array $authEndpointHeaders = null)
     {
-        $this->client = $client;
+        $this->client              = $client;
+        $this->authEndpoint        = $authEndpoint;
+        $this->authEndpointHeaders = $authEndpointHeaders;
 
         /** @var Observable $events */
         $events = $client
@@ -77,17 +90,21 @@ public function __construct(Subject $client)
     }
 
     /**
-     * @param  LoopInterface             $loop
-     * @param  string                    $app      Application ID
-     * @param  Resolver                  $resolver Optional DNS resolver
-     * @throws \InvalidArgumentException
+     * @param LoopInterface $loop
+     * @param string        $app      Application ID
+     * @param Resolver      $resolver Optional DNS resolver
+     *
      * @return AsyncClient
+     * @throws \InvalidArgumentException
      */
     public static function create(
         LoopInterface $loop,
         string $app,
         Resolver $resolver = null,
-        string $cluster = null
+        string $cluster = null,
+        string $host = null,
+        string $authEndpoint = null,
+        array $authEndpointHeaders = null,
     ): AsyncClient {
         try {
             Scheduler::setDefaultFactory(function () use ($loop) {
@@ -97,16 +114,19 @@ public static function create(
         }
 
         return new self(
-            WebSocket::createFactory(ApiSettings::createUrl($app, $cluster), false, [], $loop, $resolver)
+            WebSocket::createFactory(ApiSettings::createUrl($app, $cluster, $host), false, [], $loop, $resolver),
+            $authEndpoint,
+            $authEndpointHeaders
         );
     }
 
     /**
      * Listen on a channel.
      *
-     * @param  string                    $channel Channel to listen on
-     * @throws \InvalidArgumentException
+     * @param string $channel Channel to listen on
+     *
      * @return Observable
+     * @throws \InvalidArgumentException
      */
     public function channel(string $channel): Observable
     {
@@ -121,9 +141,15 @@ public function channel(string $channel): Observable
         });
 
         $subscribe = $this->connected
-            ->do(function () use ($channel): void {
+            ->do(function (Event $event) use ($channel): void {
+                $authKey = $channelData = null;
+
+                if (str_starts_with($channel, 'private-') || str_starts_with($channel, 'presence-')) {
+                    [$authKey, $channelData] = $this->generateAuthToken($channel, $event->getData()['socket_id']);
+                }
+
                 // Subscribe to pusher channel after connected
-                $this->send(Event::subscribeOn($channel));
+                $this->send(Event::subscribeOn($channel, $authKey, $channelData));
             })
             ->flatMapTo(Observable::empty());
 
@@ -152,7 +178,6 @@ public function channel(string $channel): Observable
      * Send a message through the client.
      *
      * @param array $message Message to send, will be json encoded
-     *
      */
     public function send(array $message): void
     {
@@ -163,7 +188,8 @@ public function send(array $message): void
      * Returns an observable of TimeoutException.
      * The timeout observable will get cancelled every time a new event is received.
      *
-     * @param  Observable $events
+     * @param Observable $events
+     *
      * @return Observable
      */
     private function timeout(Observable $events): Observable
@@ -184,20 +210,22 @@ private function timeout(Observable $events): Observable
                 }
 
                 return Observable::never()
-                    ->timeout($time)
-                    ->catch(function () use ($time) {
-                        // ping (do something that causes incoming stream to get a message)
-                        $this->send(Event::ping());
-                        // this timeout will actually timeout with a TimeoutException - causing
-                        // everything above this to dispose
-                        return Observable::never()->timeout($time);
-                    });
+                                 ->timeout($time)
+                                 ->catch(function () use ($time) {
+                                     // ping (do something that causes incoming stream to get a message)
+                                     $this->send(Event::ping());
+                                     // this timeout will actually timeout with a TimeoutException - causing
+                                     // everything above this to dispose
+                                     return Observable::never()->timeout($time);
+                                 });
             });
     }
 
     /**
      * Handle errors as described at https://pusher.com/docs/pusher_protocol#error-codes.
-     * @param  Throwable  $throwable
+     *
+     * @param Throwable $throwable
+     *
      * @return Observable
      */
     private function handleLowLevelError(Throwable $throwable): Observable
@@ -233,4 +261,44 @@ private function handleLowLevelError(Throwable $throwable): Observable
 
         return Observable::timer($this->delay);
     }
+
+    /**
+     * @throws \Exception
+     */
+    private function generateAuthToken(string $channel, string $socketId): array
+    {
+        if (!$this->authEndpoint) {
+            throw new \Exception('No auth endpoint is configured to connect private or presence channel.');
+        }
+
+        $curl = curl_init();
+
+        curl_setopt_array($curl, [
+            CURLOPT_URL            => $this->authEndpoint,
+            CURLOPT_RETURNTRANSFER => true,
+            CURLOPT_MAXREDIRS      => 10,
+            CURLOPT_TIMEOUT        => 5,
+            CURLOPT_HTTP_VERSION   => CURL_HTTP_VERSION_1_1,
+            CURLOPT_CUSTOMREQUEST  => 'POST',
+            CURLOPT_POSTFIELDS     => ['channel_name' => $channel, 'socket_id' => $socketId, 'user_data' => []],
+            CURLOPT_HTTPHEADER     => $this->authEndpointHeaders,
+        ]);
+
+        $response     = curl_exec($curl);
+        $responseCode = curl_getinfo($curl, CURLINFO_RESPONSE_CODE);
+
+        curl_close($curl);
+
+        if ($responseCode !== 200) {
+            throw new \Exception('Can\'t generate auth token for ' . $channel . '. Response code ' . $responseCode);
+        }
+
+        $response = json_decode($response, true);
+
+        if (!isset($response['auth'])) {
+            throw new \Exception('Invalid response for auth token.');
+        }
+
+        return [$response['auth'], $response['channel_data'] ?? null];
+    }
 }
diff --git a/src/Event.php b/src/Event.php
index a1a4e9b..1154164 100644
--- a/src/Event.php
+++ b/src/Event.php
@@ -33,14 +33,23 @@ public function __construct(string $event, array $data, string $channel = '')
 
     public static function createFromMessage(array $message): self
     {
+        $data = [];
+
+        if (isset($message['data'])) {
+            $data = $message['data'];
+            if (!\is_array($message['data'])) {
+                $data = \json_decode($message['data'], true);
+            }
+        }
+
         return new self(
             $message['event'],
-            \is_array($message['data']) ? $message['data'] : \json_decode($message['data'], true),
+            $data,
             $message['channel'] ?? ''
         );
     }
 
-    public function jsonSerialize()
+    public function jsonSerialize(): mixed
     {
         return \json_encode(['event' => $this->event, 'data' => $this->data, 'channel' => $this->channel]);
     }
@@ -84,9 +93,19 @@ public static function connectionEstablished(Event $event): bool
         return $event->getEvent() === 'pusher:connection_established';
     }
 
-    public static function subscribeOn(string $channel): array
+    public static function subscribeOn(string $channel, string $authKey = null, string $channelData = null): array
     {
-        return ['event' => 'pusher:subscribe', 'data' => ['channel' => $channel]];
+        $data = ['channel' => $channel];
+
+        if ($authKey) {
+            $data['auth'] = $authKey;
+        }
+
+        if ($channelData) {
+            $data['channel_data'] = $channelData;
+        }
+
+        return ['event' => 'pusher:subscribe', 'data' => $data];
     }
 
     public static function unsubscribeOn(string $channel): array