diff --git a/README.md b/README.md
index b2e7ae5..e587090 100644
--- a/README.md
+++ b/README.md
@@ -36,11 +36,11 @@
 - [ ] `PATCH /chats/{chatId}` (`editChat`) — *Редактирование информации о чате.*
 - [x] `DELETE /chats/{chatId}` (`deleteChat`) — *Удаление чата.*
 - [x] `POST /chats/{chatId}/actions` (`sendAction`) — *Отправка действия в чат (например, "печатает...").*
-- [ ] `GET /chats/{chatId}/pin` (`getPinnedMessage`) — *Получение закрепленного сообщения.*
+- [x] `GET /chats/{chatId}/pin` (`getPinnedMessage`) — *Получение закрепленного сообщения.*
 - [ ] `PUT /chats/{chatId}/pin` (`pinMessage`) — *Закрепление сообщения.*
-- [ ] `DELETE /chats/{chatId}/pin` (`unpinMessage`) — *Открепление сообщения.*
-- [ ] `GET /chats/{chatId}/members/me` (`getMembership`) — *Получение информации о членстве бота в чате.*
-- [ ] `DELETE /chats/{chatId}/members/me` (`leaveChat`) — *Выход бота из чата.*
+- [x] `DELETE /chats/{chatId}/pin` (`unpinMessage`) — *Открепление сообщения.*
+- [x] `GET /chats/{chatId}/members/me` (`getMembership`) — *Получение информации о членстве бота в чате.*
+- [x] `DELETE /chats/{chatId}/members/me` (`leaveChat`) — *Выход бота из чата.*
 - [ ] `GET /chats/{chatId}/members/admins` (`getAdmins`) — *Получение администраторов чата.*
 - [ ] `POST /chats/{chatId}/members/admins` (`postAdmins`) — *Назначение администраторов чата.*
 - [ ] `DELETE /chats/{chatId}/members/admins/{userId}` (`deleteAdmins`) — *Снятие прав администратора.*
diff --git a/src/Api.php b/src/Api.php
index 94a35fb..136dd18 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -21,6 +21,7 @@ use BushlanovDev\MaxMessengerBot\Models\Attachments\Requests\VideoAttachmentRequ
 use BushlanovDev\MaxMessengerBot\Models\BotInfo;
 use BushlanovDev\MaxMessengerBot\Models\Chat;
 use BushlanovDev\MaxMessengerBot\Models\ChatList;
+use BushlanovDev\MaxMessengerBot\Models\ChatMember;
 use BushlanovDev\MaxMessengerBot\Models\Message;
 use BushlanovDev\MaxMessengerBot\Models\MessageLink;
 use BushlanovDev\MaxMessengerBot\Models\Result;
@@ -55,6 +56,9 @@ class Api
     private const string ACTION_MESSAGES = '/messages';
     private const string ACTION_UPLOADS = '/uploads';
     private const string ACTION_CHATS = '/chats';
+    private const string ACTION_CHATS_ACTIONS = '/chats/%d/actions';
+    private const string ACTION_CHATS_PIN = '/chats/%d/pin';
+    private const string ACTION_CHATS_MEMBERS_ME = '/chats/%d/members/me';
     private const string ACTION_UPDATES = '/updates';
 
     private readonly ClientApiInterface $client;
@@ -569,10 +573,99 @@ class Api
         return $this->modelFactory->createResult(
             $this->client->request(
                 self::METHOD_POST,
-                self::ACTION_CHATS . '/' . $chatId . '/actions',
+                sprintf(self::ACTION_CHATS_ACTIONS, $chatId),
                 [],
                 ['action' => $action->value],
             )
         );
     }
+
+    /**
+     * Gets the pinned message in a chat or channel.
+     *
+     * @param int $chatId Identifier of the chat to get its pinned message from.
+     *
+     * @return Message|null
+     * @throws ClientApiException
+     * @throws NetworkException
+     * @throws ReflectionException
+     * @throws SerializationException
+     */
+    public function getPinnedMessage(int $chatId): ?Message
+    {
+        $response = $this->client->request(
+            self::METHOD_GET,
+            sprintf(self::ACTION_CHATS_PIN, $chatId),
+        );
+
+        if (!isset($response['message']) || empty($response['message'])) {
+            return null;
+        }
+
+
+        return $this->modelFactory->createMessage($response['message']);
+    }
+
+    /**
+     * Unpins a message in a chat or channel.
+     *
+     * @param int $chatId Chat identifier to remove the pinned message from.
+     *
+     * @return Result
+     * @throws ClientApiException
+     * @throws NetworkException
+     * @throws ReflectionException
+     * @throws SerializationException
+     */
+    public function unpinMessage(int $chatId): Result
+    {
+        return $this->modelFactory->createResult(
+            $this->client->request(
+                self::METHOD_DELETE,
+                sprintf(self::ACTION_CHATS_PIN, $chatId),
+            )
+        );
+    }
+
+    /**
+     * Returns chat membership info for the current bot.
+     *
+     * @param int $chatId Chat identifier.
+     *
+     * @return ChatMember
+     * @throws ClientApiException
+     * @throws NetworkException
+     * @throws ReflectionException
+     * @throws SerializationException
+     */
+    public function getMembership(int $chatId): ChatMember
+    {
+        return $this->modelFactory->createChatMember(
+            $this->client->request(
+                self::METHOD_GET,
+                sprintf(self::ACTION_CHATS_MEMBERS_ME, $chatId),
+            )
+        );
+    }
+
+    /**
+     * Removes the bot from a chat's members.
+     *
+     * @param int $chatId Chat identifier to leave from.
+     *
+     * @return Result A simple success/fail result.
+     * @throws ClientApiException
+     * @throws NetworkException
+     * @throws ReflectionException
+     * @throws SerializationException
+     */
+    public function leaveChat(int $chatId): Result
+    {
+        return $this->modelFactory->createResult(
+            $this->client->request(
+                self::METHOD_DELETE,
+                sprintf(self::ACTION_CHATS_MEMBERS_ME, $chatId),
+            )
+        );
+    }
 }
diff --git a/src/Enums/ChatAdminPermission.php b/src/Enums/ChatAdminPermission.php
new file mode 100644
index 0000000..2357fa9
--- /dev/null
+++ b/src/Enums/ChatAdminPermission.php
@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BushlanovDev\MaxMessengerBot\Enums;
+
+/**
+ * Defines the permissions an administrator can have in a chat.
+ */
+enum ChatAdminPermission: string
+{
+    case ReadAllMessages = 'read_all_messages';
+    case AddRemoveMembers = 'add_remove_members';
+    case AddAdmins = 'add_admins';
+    case ChangeChatInfo = 'change_chat_info';
+    case PinMessage = 'pin_message';
+    case Write = 'write';
+}
diff --git a/src/ModelFactory.php b/src/ModelFactory.php
index 623d8bc..2583bd2 100644
--- a/src/ModelFactory.php
+++ b/src/ModelFactory.php
@@ -8,6 +8,7 @@ use BushlanovDev\MaxMessengerBot\Enums\UpdateType;
 use BushlanovDev\MaxMessengerBot\Models\BotInfo;
 use BushlanovDev\MaxMessengerBot\Models\Chat;
 use BushlanovDev\MaxMessengerBot\Models\ChatList;
+use BushlanovDev\MaxMessengerBot\Models\ChatMember;
 use BushlanovDev\MaxMessengerBot\Models\Message;
 use BushlanovDev\MaxMessengerBot\Models\Result;
 use BushlanovDev\MaxMessengerBot\Models\Subscription;
@@ -192,4 +193,17 @@ class ModelFactory
     {
         return ChatList::fromArray($data);
     }
+
+    /**
+     * Creates a ChatMember object from raw API data.
+     *
+     * @param array<string, mixed> $data
+     *
+     * @return ChatMember
+     * @throws ReflectionException
+     */
+    public function createChatMember(array $data): ChatMember
+    {
+        return ChatMember::fromArray($data);
+    }
 }
diff --git a/src/Models/ChatMember.php b/src/Models/ChatMember.php
new file mode 100644
index 0000000..a9cf1a4
--- /dev/null
+++ b/src/Models/ChatMember.php
@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BushlanovDev\MaxMessengerBot\Models;
+
+use BushlanovDev\MaxMessengerBot\Attributes\ArrayOf;
+use BushlanovDev\MaxMessengerBot\Enums\ChatAdminPermission;
+
+/**
+ * Represents a member of a chat, including their user information and chat-specific status.
+ */
+final readonly class ChatMember extends AbstractModel
+{
+    /**
+     * @param int $userId User's identifier.
+     * @param string $firstName User's first name.
+     * @param string|null $lastName User's last name.
+     * @param string|null $username User's public username.
+     * @param bool $isBot True if the user is a bot.
+     * @param int $lastActivityTime Time of the user's last activity in Max.
+     * @param string|null $description User's profile description.
+     * @param string|null $avatarUrl URL of the user's avatar.
+     * @param string|null $fullAvatarUrl URL of the user's full-sized avatar.
+     * @param int $lastAccessTime The time the user last accessed the chat.
+     * @param bool $isOwner True if this member is the owner of the chat.
+     * @param bool $isAdmin True if this member is an administrator of the chat.
+     * @param int $joinTime The time the user joined the chat.
+     * @param ChatAdminPermission[]|null $permissions A list of permissions if the member is an admin, otherwise null.
+     */
+    public function __construct(
+        public int $userId,
+        public string $firstName,
+        public ?string $lastName,
+        public ?string $username,
+        public bool $isBot,
+        public int $lastActivityTime,
+        public ?string $description,
+        public ?string $avatarUrl,
+        public ?string $fullAvatarUrl,
+        public int $lastAccessTime,
+        public bool $isOwner,
+        public bool $isAdmin,
+        public int $joinTime,
+        #[ArrayOf(ChatAdminPermission::class)]
+        public ?array $permissions,
+    ) {
+    }
+}
diff --git a/tests/ApiTest.php b/tests/ApiTest.php
index 95c219b..9c39bfc 100644
--- a/tests/ApiTest.php
+++ b/tests/ApiTest.php
@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace BushlanovDev\MaxMessengerBot\Tests;
 
 use BushlanovDev\MaxMessengerBot\Api;
+use BushlanovDev\MaxMessengerBot\Attributes\ArrayOf;
 use BushlanovDev\MaxMessengerBot\Client;
 use BushlanovDev\MaxMessengerBot\ClientApiInterface;
 use BushlanovDev\MaxMessengerBot\Enums\AttachmentType;
@@ -36,6 +37,7 @@ use BushlanovDev\MaxMessengerBot\Models\Attachments\Requests\VideoAttachmentRequ
 use BushlanovDev\MaxMessengerBot\Models\BotInfo;
 use BushlanovDev\MaxMessengerBot\Models\Chat;
 use BushlanovDev\MaxMessengerBot\Models\ChatList;
+use BushlanovDev\MaxMessengerBot\Models\ChatMember;
 use BushlanovDev\MaxMessengerBot\Models\Message;
 use BushlanovDev\MaxMessengerBot\Models\MessageBody;
 use BushlanovDev\MaxMessengerBot\Models\Recipient;
@@ -101,6 +103,8 @@ use RuntimeException;
 #[UsesClass(ShareAttachmentRequest::class)]
 #[UsesClass(ShareAttachmentRequestPayload::class)]
 #[UsesClass(ChatList::class)]
+#[UsesClass(ChatMember::class)]
+#[UsesClass(ArrayOf::class)]
 final class ApiTest extends TestCase
 {
     use PHPMock;
@@ -1354,4 +1358,146 @@ final class ApiTest extends TestCase
         $result = $this->api->sendAction($chatId, $action);
         $this->assertSame($expectedResult, $result);
     }
+
+    #[Test]
+    public function getPinnedMessageReturnsMessageOnSuccess(): void
+    {
+        $chatId = 12345;
+        $uri = '/chats/' . $chatId . '/pin';
+
+        $messageData = [
+            'timestamp' => 1,
+            'body' => ['mid' => 'pinned.msg', 'seq' => 1],
+            'recipient' => ['chat_type' => 'chat', 'chat_id' => $chatId],
+        ];
+        $rawResponse = ['message' => $messageData];
+
+        $expectedMessage = Message::fromArray($messageData);
+
+        $this->clientMock->expects($this->once())
+            ->method('request')
+            ->with('GET', $uri)
+            ->willReturn($rawResponse);
+
+        $this->modelFactoryMock->expects($this->once())
+            ->method('createMessage')
+            ->with($messageData)
+            ->willReturn($expectedMessage);
+
+        $actualMessage = $this->api->getPinnedMessage($chatId);
+
+        $this->assertSame($expectedMessage, $actualMessage);
+    }
+
+    #[Test]
+    public function getPinnedMessageReturnsNullWhenNoMessageIsPinned(): void
+    {
+        $chatId = 54321;
+        $uri = '/chats/' . $chatId . '/pin';
+        $rawResponse = ['message' => null];
+
+        $this->clientMock->expects($this->once())
+            ->method('request')
+            ->with('GET', $uri)
+            ->willReturn($rawResponse);
+
+        $this->modelFactoryMock->expects($this->never())
+            ->method('createMessage');
+
+        $result = $this->api->getPinnedMessage($chatId);
+
+        $this->assertNull($result);
+    }
+
+    #[Test]
+    public function unpinMessageCallsClientCorrectly(): void
+    {
+        $chatId = 98765;
+        $uri = '/chats/' . $chatId . '/pin';
+        $rawResponse = ['success' => true, 'message' => null];
+        $expectedResult = new Result(true, null);
+
+        $this->clientMock
+            ->expects($this->once())
+            ->method('request')
+            ->with(self::equalTo('DELETE'), self::equalTo($uri))
+            ->willReturn($rawResponse);
+
+        $this->modelFactoryMock
+            ->expects($this->once())
+            ->method('createResult')
+            ->with($rawResponse)
+            ->willReturn($expectedResult);
+
+        $result = $this->api->unpinMessage($chatId);
+
+        $this->assertSame($expectedResult, $result);
+        $this->assertTrue($result->success);
+    }
+
+    #[Test]
+    public function getMembershipReturnsCorrectChatMember(): void
+    {
+        $chatId = 12345;
+        $uri = sprintf('/chats/%d/members/me', $chatId);
+
+        $rawResponse = [
+            'user_id' => 1,
+            'first_name' => 'MyBot',
+            'is_bot' => true,
+            'last_activity_time' => 1,
+            'last_name' => null,
+            'username' => 'my_bot',
+            'description' => null,
+            'avatar_url' => null,
+            'full_avatar_url' => null,
+            'last_access_time' => 2,
+            'is_owner' => false,
+            'is_admin' => true,
+            'join_time' => 0,
+            'permissions' => ['write'],
+        ];
+        $expectedMember = ChatMember::fromArray($rawResponse);
+
+        $this->clientMock
+            ->expects($this->once())
+            ->method('request')
+            ->with('GET', $uri)
+            ->willReturn($rawResponse);
+
+        $this->modelFactoryMock
+            ->expects($this->once())
+            ->method('createChatMember')
+            ->with($rawResponse)
+            ->willReturn($expectedMember);
+
+        $result = $this->api->getMembership($chatId);
+
+        $this->assertSame($expectedMember, $result);
+    }
+
+    #[Test]
+    public function leaveChatCallsClientCorrectly(): void
+    {
+        $chatId = 54321;
+        $uri = sprintf('/chats/%d/members/me', $chatId);
+        $rawResponse = ['success' => true];
+        $expectedResult = new Result(true, null);
+
+        $this->clientMock
+            ->expects($this->once())
+            ->method('request')
+            ->with(self::equalTo('DELETE'), self::equalTo($uri))
+            ->willReturn($rawResponse);
+
+        $this->modelFactoryMock
+            ->expects($this->once())
+            ->method('createResult')
+            ->with($rawResponse)
+            ->willReturn($expectedResult);
+
+        $result = $this->api->leaveChat($chatId);
+
+        $this->assertSame($expectedResult, $result);
+    }
 }
diff --git a/tests/ModelFactoryTest.php b/tests/ModelFactoryTest.php
index 5c92383..8b750d4 100644
--- a/tests/ModelFactoryTest.php
+++ b/tests/ModelFactoryTest.php
@@ -5,12 +5,14 @@ declare(strict_types=1);
 namespace BushlanovDev\MaxMessengerBot\Tests;
 
 use BushlanovDev\MaxMessengerBot\Attributes\ArrayOf;
+use BushlanovDev\MaxMessengerBot\Enums\ChatAdminPermission;
 use BushlanovDev\MaxMessengerBot\Enums\UpdateType;
 use BushlanovDev\MaxMessengerBot\ModelFactory;
 use BushlanovDev\MaxMessengerBot\Models\BotCommand;
 use BushlanovDev\MaxMessengerBot\Models\BotInfo;
 use BushlanovDev\MaxMessengerBot\Models\Chat;
 use BushlanovDev\MaxMessengerBot\Models\ChatList;
+use BushlanovDev\MaxMessengerBot\Models\ChatMember;
 use BushlanovDev\MaxMessengerBot\Models\Image;
 use BushlanovDev\MaxMessengerBot\Models\Message;
 use BushlanovDev\MaxMessengerBot\Models\MessageBody;
@@ -50,6 +52,7 @@ use PHPUnit\Framework\TestCase;
 #[UsesClass(ChatTitleChangedUpdate::class)]
 #[UsesClass(MessageChatCreatedUpdate::class)]
 #[UsesClass(ChatList::class)]
+#[UsesClass(ChatMember::class)]
 final class ModelFactoryTest extends TestCase
 {
     private ModelFactory $factory;
@@ -351,4 +354,36 @@ final class ModelFactoryTest extends TestCase
         $this->assertInstanceOf(Chat::class, $chatList->chats[0]);
         $this->assertSame(101, $chatList->chats[0]->chatId);
     }
+
+    #[Test]
+    public function createChatMember()
+    {
+        $rawData = [
+            'user_id' => 101,
+            'first_name' => 'AdminBot',
+            'last_name' => null,
+            'username' => 'admin_bot',
+            'is_bot' => true,
+            'last_activity_time' => 1678886400,
+            'description' => 'I am a bot.',
+            'avatar_url' => null,
+            'full_avatar_url' => null,
+            'last_access_time' => 1679000000,
+            'is_owner' => false,
+            'is_admin' => true,
+            'join_time' => 1678000000,
+            'permissions' => ['pin_message', 'write'],
+        ];
+
+        $chatMember = $this->factory->createChatMember($rawData);
+
+        $this->assertInstanceOf(ChatMember::class, $chatMember);
+        $this->assertTrue($chatMember->isAdmin);
+        $this->assertFalse($chatMember->isOwner);
+        $this->assertIsArray($chatMember->permissions);
+        $this->assertCount(2, $chatMember->permissions);
+        $this->assertSame(ChatAdminPermission::PinMessage, $chatMember->permissions[0]);
+        $this->assertSame(ChatAdminPermission::Write, $chatMember->permissions[1]);
+        $this->assertEquals($rawData, $chatMember->toArray());
+    }
 }
diff --git a/tests/Models/ChatMemberTest.php b/tests/Models/ChatMemberTest.php
new file mode 100644
index 0000000..4f207e0
--- /dev/null
+++ b/tests/Models/ChatMemberTest.php
@@ -0,0 +1,77 @@
+<?php
+
+declare(strict_types=1);
+
+namespace BushlanovDev\MaxMessengerBot\Tests\Models;
+
+use BushlanovDev\MaxMessengerBot\Attributes\ArrayOf;
+use BushlanovDev\MaxMessengerBot\Enums\ChatAdminPermission;
+use BushlanovDev\MaxMessengerBot\Models\ChatMember;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\Attributes\UsesClass;
+use PHPUnit\Framework\TestCase;
+
+#[CoversClass(ChatMember::class)]
+#[UsesClass(ArrayOf::class)]
+final class ChatMemberTest extends TestCase
+{
+    #[Test]
+    public function canBeCreatedForAdmin(): void
+    {
+        $data = [
+            'user_id' => 101,
+            'first_name' => 'AdminBot',
+            'last_name' => null,
+            'username' => 'admin_bot',
+            'is_bot' => true,
+            'last_activity_time' => 1678886400,
+            'description' => 'I am a bot.',
+            'avatar_url' => null,
+            'full_avatar_url' => null,
+            'last_access_time' => 1679000000,
+            'is_owner' => false,
+            'is_admin' => true,
+            'join_time' => 1678000000,
+            'permissions' => ['pin_message', 'write'],
+        ];
+
+        $member = ChatMember::fromArray($data);
+
+        $this->assertInstanceOf(ChatMember::class, $member);
+        $this->assertTrue($member->isAdmin);
+        $this->assertFalse($member->isOwner);
+        $this->assertIsArray($member->permissions);
+        $this->assertCount(2, $member->permissions);
+        $this->assertSame(ChatAdminPermission::PinMessage, $member->permissions[0]);
+        $this->assertSame(ChatAdminPermission::Write, $member->permissions[1]);
+        $this->assertEquals($data, $member->toArray());
+    }
+
+    #[Test]
+    public function canBeCreatedForRegularMember(): void
+    {
+        $data = [
+            'user_id' => 102,
+            'first_name' => 'RegularUser',
+            'last_name' => 'Smith',
+            'username' => 'regular_user',
+            'is_bot' => false,
+            'last_activity_time' => 1678886401,
+            'description' => null,
+            'avatar_url' => 'http://example.com/avatar.png',
+            'full_avatar_url' => 'http://example.com/avatar_full.png',
+            'last_access_time' => 1679000001,
+            'is_owner' => false,
+            'is_admin' => false,
+            'join_time' => 1678000001,
+            'permissions' => null,
+        ];
+
+        $member = ChatMember::fromArray($data);
+
+        $this->assertFalse($member->isAdmin);
+        $this->assertNull($member->permissions);
+        $this->assertEquals($data, $member->toArray());
+    }
+}