diff --git a/src/PushNotifications.php b/src/PushNotifications.php
index dcdbe89..6c332f0 100644
--- a/src/PushNotifications.php
+++ b/src/PushNotifications.php
@@ -9,7 +9,7 @@
  * Used to publish notifications to the Pusher Push Notifications API
  * http://www.pusher.com/push-notifications
  */
-class PushNotifications {
+class PushNotifications implements PushNotificationsInterface {
   const SDK_VERSION = "2.0.0";
   const MAX_INTERESTS = 100;
   const MAX_INTEREST_LENGTH = 164;
diff --git a/src/PushNotificationsInterface.php b/src/PushNotificationsInterface.php
new file mode 100644
index 0000000..da4dbee
--- /dev/null
+++ b/src/PushNotificationsInterface.php
@@ -0,0 +1,63 @@
+<?php
+
+namespace Pusher\PushNotifications;
+
+/**
+ * Used to publish notifications to the Pusher Push Notifications API
+ *
+ * @see http://www.pusher.com/push-notifications
+ */
+interface PushNotificationsInterface
+{
+    /**
+     * Sends broadcast notifications to groups of subscribed devices using Device Interests.
+     *
+     * @param array $interests
+     *   Array of interests to send the push notification to, ranging from 1 to 100 per publish request.
+     * @param array<string> $publishRequest
+     *   An array of parameters to add to the request body
+     *
+     * @return mixed
+     *   An array containing the publish response body.
+     *
+     * @throws \Exception
+     * @see https://pusher.com/docs/beams/concepts/device-interests
+     */
+    public function publishToInterests(array $interests, array $publishRequest): mixed;
+
+    /**
+     * Securely send notifications to individual users of your application using Authenticated Users.
+     *
+     * @param array $userIds
+     *   Array of ids of users to send the push notification to, ranging from 1 to 1000 per publish request.
+     * @param array<string> $publishRequest
+     *   An array of parameters to add to the request body
+     *
+     * @return mixed
+     *   An array containing the publish response body.
+     *
+     * @throws \Exception
+     */
+    public function publishToUsers(array $userIds, array $publishRequest): mixed;
+
+    /**
+     * Remove the given user (and all of their devices) from Beams. This user will no longer receive any notifications and all state stored about their devices will be deleted.
+     *
+     * @param string $userId
+     *   The id of the user you would like to remove from Beams.
+     *
+     * @throws \Exception
+     */
+    public function deleteUser(string $userId): void;
+
+    /**
+     * Generate a Beams auth token to allow a user to associate their device with their user id. The token is valid for 24 hours.
+     *
+     * @param string $userId
+     *   The id of the user you would like to generate a Beams auth token for.
+     *
+     * @return array
+     *   An array containing the token key.
+     */
+    public function generateToken(string $userId): array;
+}