diff --git a/lib/Contracts/IMailManager.php b/lib/Contracts/IMailManager.php
index d7ee53837b..27124b246f 100644
--- a/lib/Contracts/IMailManager.php
+++ b/lib/Contracts/IMailManager.php
@@ -22,8 +22,22 @@
 namespace OCA\Mail\Contracts;
 
 use OCA\Mail\Account;
+use OCA\Mail\Folder;
+use OCA\Mail\IMAP\Sync\Request as SyncRequest;
+use OCA\Mail\IMAP\Sync\Response as SyncResponse;
 
 interface IMailManager {
 
+	/**
+	 * @param Account $account
+	 * @return Folder[]
+	 */
 	public function getFolders(Account $account);
+
+	/**
+	 * @param Account
+	 * @param SyncRequest $syncRequest
+	 * @return SyncResponse
+	 */
+	public function syncMessages(Account $account, SyncRequest $syncRequest);
 }
diff --git a/lib/IMAP/MessageMapper.php b/lib/IMAP/MessageMapper.php
new file mode 100644
index 0000000000..61b62ed406
--- /dev/null
+++ b/lib/IMAP/MessageMapper.php
@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\IMAP;
+
+use Exception;
+use Horde_Imap_Client_Base;
+use OCA\Mail\Folder;
+use OCA\Mail\Model\IMAPMessage;
+
+class MessageMapper {
+
+	/**
+	 * @param Horde_Imap_Client_Base $imapClient
+	 * @param Folder $mailbox
+	 * @param array $ids
+	 * @return IMAPMessage[]
+	 */
+	public function findByIds(Horde_Imap_Client_Base $imapClient, $mailbox, array $ids) {
+		throw new Exception('not implemented');
+	}
+
+}
diff --git a/lib/IMAP/Sync/Request.php b/lib/IMAP/Sync/Request.php
new file mode 100644
index 0000000000..59de0d65cc
--- /dev/null
+++ b/lib/IMAP/Sync/Request.php
@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\IMAP\Sync;
+
+class Request {
+
+	/** @var string */
+	private $mailbox;
+
+	/** @var string */
+	private $syncToken;
+
+	/**
+	 * @param string $mailbox
+	 * @param string $syncToken
+	 */
+	public function __construct($mailbox, $syncToken) {
+		$this->mailbox = $mailbox;
+		$this->syncToken = $syncToken;
+	}
+
+	/**
+	 * Get the mailbox name
+	 *
+	 * @return string
+	 */
+	public function getMailbox() {
+		return $this->mailbox;
+	}
+
+	/**
+	 * @return string the Horde sync token
+	 */
+	public function getToken() {
+		return $this->syncToken;
+	}
+
+}
diff --git a/lib/IMAP/Sync/Response.php b/lib/IMAP/Sync/Response.php
new file mode 100644
index 0000000000..a267b84e8f
--- /dev/null
+++ b/lib/IMAP/Sync/Response.php
@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\IMAP\Sync;
+
+use Exception;
+use JsonSerializable;
+use OCA\Mail\Model\IMAPMessage;
+
+class Response implements JsonSerializable {
+
+	/** @var string */
+	private $syncToken;
+
+	/** @var IMAPMessage[] */
+	private $newMessages;
+
+	/** @var IMAPMessage[] */
+	private $changedMessages;
+
+	/** @var array */
+	private $vanishedMessages;
+
+	/**
+	 * @param string $syncToken
+	 * @param IMAPMessage[] $newMessages
+	 * @param IMAPMessage[] $changedMessages
+	 * @param array $vanishedMessages
+	 */
+	public function __construct($syncToken, array $newMessages = [], array $changedMessages = [],
+		array $vanishedMessages = []) {
+		$this->syncToken = $syncToken;
+		$this->newMessages = $newMessages;
+		$this->changedMessages = $changedMessages;
+		$this->vanishedMessages = $vanishedMessages;
+	}
+
+	/**
+	 * @return array
+	 */
+	public function jsonSerialize() {
+		return [
+			'newMessages' => $this->newMessages,
+			'changedMessages' => $this->changedMessages,
+			'vanishedMessages' => $this->vanishedMessages,
+			'token' => $this->syncToken,
+		];
+	}
+
+}
diff --git a/lib/IMAP/Sync/Synchronizer.php b/lib/IMAP/Sync/Synchronizer.php
new file mode 100644
index 0000000000..840d8ec592
--- /dev/null
+++ b/lib/IMAP/Sync/Synchronizer.php
@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\IMAP\Sync;
+
+use Horde_Imap_Client_Base;
+use OCA\Mail\IMAP\MessageMapper;
+use OCA\Mail\IMAP\Sync\Request;
+use OCA\Mail\IMAP\Sync\Response;
+
+class Synchronizer {
+
+	/** @var MessageMapper */
+	private $messageMapper;
+
+	/**
+	 * @param MessageMapper $messageMapper
+	 */
+	public function __construct(MessageMapper $messageMapper) {
+		$this->messageMapper = $messageMapper;
+	}
+
+	/**
+	 * @param Horde_Imap_Client_Base $imapClient
+	 * @param Request $request
+	 * @return Response
+	 */
+	public function sync(Horde_Imap_Client_Base $imapClient, Request $request) {
+		$hordeSync = $imapClient->sync($request->getMailbox(), $request->getToken());
+
+		$newMessages = $this->messageMapper->findByIds($imapClient, $request->getMailbox(), $hordeSync->newmsgsuids->ids);
+		$changedMessages = $this->messageMapper->findByIds($imapClient, $request->getMailbox(), $hordeSync->flagsuids->ids);
+		$vanishedMessages = $hordeSync->vanisheduids->ids;
+
+		$newSyncToken = $imapClient->getSyncToken($request->getMailbox());
+		return new Response($newSyncToken, $newMessages, $changedMessages, $vanishedMessages);
+	}
+
+}
diff --git a/lib/Service/MailManager.php b/lib/Service/MailManager.php
index f04022074d..906bae0bfd 100644
--- a/lib/Service/MailManager.php
+++ b/lib/Service/MailManager.php
@@ -1,5 +1,6 @@
 <?php
 
+
 /**
  * @author Christoph Wurst <christoph@winzerhof-wurst.at>
  *
@@ -24,7 +25,12 @@
 use OCA\Mail\Account;
 use OCA\Mail\Contracts\IMailManager;
 use OCA\Mail\Folder;
-use OCA\Mail\Service\IMAP\IMAPClientFactory;
+use OCA\Mail\IMAP\IMAPClientFactory;
+use OCA\Mail\IMAP\Sync\Request;
+use OCA\Mail\IMAP\Sync\Response;
+use OCA\Mail\IMAP\Sync\Synchronizer;
+use OCA\Mail\Service\FolderMapper;
+use OCA\Mail\Service\FolderNameTranslator;
 
 class MailManager implements IMailManager {
 
@@ -37,16 +43,21 @@ class MailManager implements IMailManager {
 	/** @var FolderNameTranslator */
 	private $folderNameTranslator;
 
+	/** @var Synchronizer */
+	private $synchronizer;
+
 	/**
 	 * @param IMAPClientFactory $imapClientFactory
 	 * @param FolderMapper $folderMapper
-	 * @param FolderNameTranslator
+	 * @param FolderNameTranslator $folderNameTranslator
+	 * @param Synchronizer $synchronizer
 	 */
-	public function __construct(IMAPClientFactory $imapClientFactory,
-		FolderMapper $folderMapper, FolderNameTranslator $folderNameTranslator) {
+	public function __construct(IMAPClientFactory $imapClientFactory, FolderMapper $folderMapper,
+		FolderNameTranslator $folderNameTranslator, Synchronizer $synchronizer) {
 		$this->imapClientFactory = $imapClientFactory;
 		$this->folderMapper = $folderMapper;
 		$this->folderNameTranslator = $folderNameTranslator;
+		$this->synchronizer = $synchronizer;
 	}
 
 	/**
@@ -64,4 +75,15 @@ public function getFolders(Account $account) {
 		return $this->folderMapper->buildFolderHierarchy($folders);
 	}
 
+	/**
+	 * @param Account $account
+	 * @param Request $syncRequest
+	 * @return Response
+	 */
+	public function syncMessages(Account $account, Request $syncRequest) {
+		$client = $this->imapClientFactory->getClient($account);
+
+		return $this->synchronizer->sync($client, $syncRequest);
+	}
+
 }
diff --git a/tests/IMAP/Sync/RequestTest.php b/tests/IMAP/Sync/RequestTest.php
new file mode 100644
index 0000000000..e54d5703fa
--- /dev/null
+++ b/tests/IMAP/Sync/RequestTest.php
@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\Tests\IMAP\Sync;
+
+use OCA\Mail\IMAP\Sync\Request;
+use PHPUnit_Framework_TestCase;
+
+class RequestTest extends PHPUnit_Framework_TestCase {
+
+	/** @var string */
+	private $mailbox;
+
+	/** @var string */
+	private $syncToken;
+
+	/** @var Request */
+	private $request;
+
+	protected function setUp() {
+		parent::setUp();
+
+		$this->mailbox = 'inbox';
+		$this->syncToken = 'ab123';
+
+		$this->request = new Request($this->mailbox, $this->syncToken);
+	}
+
+	public function testGetMailbox() {
+		$this->assertEquals($this->mailbox, $this->request->getMailbox());
+	}
+
+	public function testGetSyncToken() {
+		$this->assertEquals($this->syncToken, $this->request->getToken());
+	}
+
+}
diff --git a/tests/IMAP/Sync/ResponseTest.php b/tests/IMAP/Sync/ResponseTest.php
new file mode 100644
index 0000000000..d9b4741ce9
--- /dev/null
+++ b/tests/IMAP/Sync/ResponseTest.php
@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\Tests\IMAP\Sync;
+
+use OCA\Mail\IMAP\Sync\Response;
+use PHPUnit_Framework_TestCase;
+
+class ResponseTest extends PHPUnit_Framework_TestCase {
+
+	public function testJsonSerialize() {
+		$newMessages = [];
+		$changedMessages = [];
+		$vanishedMessages = [];
+		$syncToken = 'bc4564';
+		$response = new Response($syncToken, $newMessages, $changedMessages, $vanishedMessages);
+		$expected = [
+			'newMessages' => [],
+			'changedMessages' => [],
+			'vanishedMessages' => [],
+			'token' => $syncToken,
+		];
+
+		$json = $response->jsonSerialize();
+
+		$this->assertEquals($expected, $json);
+	}
+
+}
diff --git a/tests/IMAP/Sync/SynchronizerTest.php b/tests/IMAP/Sync/SynchronizerTest.php
new file mode 100644
index 0000000000..a6381c0b15
--- /dev/null
+++ b/tests/IMAP/Sync/SynchronizerTest.php
@@ -0,0 +1,91 @@
+<?php
+
+/**
+ * @author Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * Mail
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OCA\Mail\Tests\IMAP\Sync;
+
+use Horde_Imap_Client_Base;
+use Horde_Imap_Client_Data_Sync;
+use Horde_Imap_Client_Ids;
+use OCA\Mail\IMAP\MessageMapper;
+use OCA\Mail\IMAP\Sync\Request;
+use OCA\Mail\IMAP\Sync\Response;
+use OCA\Mail\IMAP\Sync\Synchronizer;
+use PHPUnit_Framework_MockObject_MockObject;
+use PHPUnit_Framework_TestCase;
+
+class SynchronizerTest extends PHPUnit_Framework_TestCase {
+
+	/** @var MessageMapper|PHPUnit_Framework_MockObject_MockObject */
+	private $messageMapper;
+
+	/** @var Synchronizer */
+	private $synchronizer;
+
+	protected function setUp() {
+		parent::setUp();
+
+		$this->messageMapper = $this->createMock(MessageMapper::class);
+
+		$this->synchronizer = new Synchronizer($this->messageMapper);
+	}
+
+	private function getHordeMessageIdMock(array $ids) {
+		$hordeIds = $this->createMock(Horde_Imap_Client_Ids::class);
+		$hordeIds->ids = $ids;
+		return $hordeIds;
+	}
+
+	public function testSync() {
+		$imapClient = $this->createMock(Horde_Imap_Client_Base::class);
+		$request = $this->createMock(Request::class);
+		$request->expects($this->any())
+			->method('getMailbox')
+			->willReturn('inbox');
+		$request->expects($this->once())
+			->method('getToken')
+			->willReturn('123456');
+		$hordeSync = $this->createMock(Horde_Imap_Client_Data_Sync::class);
+		$imapClient->expects($this->once())
+			->method('sync')
+			->with($this->equalTo('inbox'), $this->equalTo('123456'))
+			->willReturn($hordeSync);
+		$newMessages = [];
+		$changedMessages = [];
+		$vanishedMessages = [4, 5];
+		$hordeSync->newmsgsuids = $this->getHordeMessageIdMock($newMessages);
+		$hordeSync->flagsuids = $this->getHordeMessageIdMock($changedMessages);
+		$hordeSync->vanisheduids = $this->getHordeMessageIdMock($vanishedMessages);
+		$this->messageMapper->expects($this->exactly(2))
+			->method('findByIds')
+			->with($imapClient, $this->equalTo('inbox'), $this->equalTo([]))
+			->willReturn([]);
+		$imapClient->expects($this->once())
+			->method('getSyncToken')
+			->with($this->equalTo('inbox'))
+			->willReturn('54321');
+		$expected = new Response('54321', $newMessages, $changedMessages, $vanishedMessages);
+
+		$response = $this->synchronizer->sync($imapClient, $request);
+
+		$this->assertEquals($expected, $response);
+	}
+
+}