diff --git a/src/Api/Workspaces/Projects.php b/src/Api/Workspaces/Projects.php
index fa5d454..921668f 100644
--- a/src/Api/Workspaces/Projects.php
+++ b/src/Api/Workspaces/Projects.php
@@ -13,6 +13,8 @@
 
 namespace Bitbucket\Api\Workspaces;
 
+use Bitbucket\Api\Workspaces\Projects\GroupPermissions;
+use Bitbucket\Api\Workspaces\Projects\UserPermissions;
 use Bitbucket\HttpClient\Util\UriBuilder;
 
 /**
@@ -95,6 +97,22 @@ public function remove(string $project, array $params = [])
         return $this->delete($uri, $params);
     }
 
+    /**
+     * @return UserPermissions
+     */
+    public function userPermissions(string $project): UserPermissions
+    {
+        return new UserPermissions($this->getClient(), $this->workspace, $project);
+    }
+
+    /**
+     * @return GroupPermissions
+     */
+    public function groupPermissions(string $project): GroupPermissions
+    {
+        return new GroupPermissions($this->getClient(), $this->workspace, $project);
+    }
+
     /**
      * Build the projects URI from the given parts.
      *
diff --git a/src/Api/Workspaces/Projects/AbstractProjectsApi.php b/src/Api/Workspaces/Projects/AbstractProjectsApi.php
new file mode 100644
index 0000000..ae5728d
--- /dev/null
+++ b/src/Api/Workspaces/Projects/AbstractProjectsApi.php
@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the Bitbucket API Client.
+ *
+ * (c) Graham Campbell <hello@gjcampbell.co.uk>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Bitbucket\Api\Workspaces\Projects;
+
+use Bitbucket\Api\Workspaces\AbstractWorkspacesApi;
+use Bitbucket\Client;
+
+/**
+ * The abstract projects API class.
+ *
+ * @author Patrick Barsallo <p.d.barsallo@gmail.com>
+ */
+abstract class AbstractProjectsApi extends AbstractWorkspacesApi
+{
+
+    /**
+     * The project.
+     *
+     * @var string
+     */
+    protected $project;
+
+    /**
+     * Create a new API instance.
+     *
+     * @param Client $client
+     * @param string $project
+     *
+     * @return void
+     */
+    public function __construct(Client $client, string $workspace, string $project)
+    {
+        parent::__construct($client, $workspace);
+        $this->project = $project;
+    }
+}
diff --git a/src/Api/Workspaces/Projects/GroupPermissions.php b/src/Api/Workspaces/Projects/GroupPermissions.php
new file mode 100644
index 0000000..f3599e1
--- /dev/null
+++ b/src/Api/Workspaces/Projects/GroupPermissions.php
@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the Bitbucket API Client.
+ *
+ * (c) Graham Campbell <hello@gjcampbell.co.uk>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Bitbucket\Api\Workspaces\Projects;
+
+use Bitbucket\HttpClient\Util\UriBuilder;
+
+/**
+ * The branch restrictions API class.
+ *
+ * @author Graham Campbell <hello@gjcampbell.co.uk>
+ */
+class GroupPermissions extends AbstractProjectsApi
+{
+    /**
+     * @param array $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function list(array $params = [])
+    {
+        $uri = $this->buildGroupsUri();
+
+        return $this->get($uri, $params);
+    }
+
+    /**
+     * @param string $group
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function show(string $group, array $params = [])
+    {
+        $uri = $this->buildGroupsUri($group);
+
+        return $this->get($uri, $params);
+    }
+
+    /**
+     * @param string $group
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function update(string $group, array $params = [])
+    {
+        $uri = $this->buildGroupsUri($group);
+
+        return $this->put($uri, $params);
+    }
+
+    /**
+     * @param string $group
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function remove(string $group, array $params = [])
+    {
+        $uri = $this->buildGroupsUri($group);
+
+        return $this->delete($uri, $params);
+    }
+
+    /**
+     * Build the groups URI from the given parts.
+     *
+     * @param string ...$parts
+     *
+     * @return string
+     */
+    public function buildGroupsUri(string ...$parts): string
+    {
+        return UriBuilder::build('workspaces', $this->workspace, 'projects', $this->project, 'permissions-config/groups', ...$parts);
+    }
+}
diff --git a/src/Api/Workspaces/Projects/UserPermissions.php b/src/Api/Workspaces/Projects/UserPermissions.php
new file mode 100644
index 0000000..d951c77
--- /dev/null
+++ b/src/Api/Workspaces/Projects/UserPermissions.php
@@ -0,0 +1,110 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the Bitbucket API Client.
+ *
+ * (c) Graham Campbell <hello@gjcampbell.co.uk>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Bitbucket\Api\Workspaces\Projects;
+
+use Bitbucket\HttpClient\Util\UriBuilder;
+
+/**
+ * The branch restrictions API class.
+ *
+ * @author Graham Campbell <hello@gjcampbell.co.uk>
+ */
+class UserPermissions extends AbstractProjectsApi
+{
+    /**
+     * @param array $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function list(array $params = [])
+    {
+        $uri = $this->buildUsersUri();
+
+        return $this->get($uri, $params);
+    }
+
+    /**
+     * @param string $user
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function show(string $user, array $params = [])
+    {
+        $uri = $this->buildUsersUri($user);
+
+        return $this->get($uri, $params);
+    }
+
+    /**
+     * @param string $user
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function create(string $user, array $params = [])
+    {
+        $uri = $this->buildUsersUri($user);
+
+        return $this->put($uri, $params);
+    }
+
+    /**
+     * @param string $user
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function update(string $user, array $params = [])
+    {
+        $uri = $this->buildUsersUri($user);
+
+        return $this->put($uri, $params);
+    }
+
+    /**
+     * @param string $user
+     * @param array  $params
+     *
+     * @throws \Http\Client\Exception
+     *
+     * @return array
+     */
+    public function remove(string $user, array $params = [])
+    {
+        $uri = $this->buildUsersUri($user);
+
+        return $this->delete($uri, $params);
+    }
+
+    /**
+     * Build the groups URI from the given parts.
+     *
+     * @param string ...$parts
+     *
+     * @return string
+     */
+    public function buildUsersUri(string ...$parts): string
+    {
+        return UriBuilder::build('workspaces', $this->workspace, 'projects', $this->project, 'permissions-config/users', ...$parts);
+    }
+}