diff --git a/tests/Client/ClientTest.php b/tests/Client/ClientTest.php
index 3d08f6f..4f854c3 100644
--- a/tests/Client/ClientTest.php
+++ b/tests/Client/ClientTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Pop\Mail\Test\Transport;
+namespace Pop\Mail\Test\Client;
 
 use Pop\Http;
 use Pop\Mail\Client;
diff --git a/tests/Client/GoogleTest.php b/tests/Client/GoogleTest.php
new file mode 100644
index 0000000..35e9fa8
--- /dev/null
+++ b/tests/Client/GoogleTest.php
@@ -0,0 +1,162 @@
+<?php
+
+namespace Pop\Mail\Test\Client;
+
+use Pop\Http;
+use Pop\Mail\Client;
+use PHPUnit\Framework\TestCase;
+
+class GoogleTest extends TestCase
+{
+
+    public function testGetMessages1()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $messages = $google->getMessages();
+    }
+
+    public function testGetMessages2()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $search = [
+            'subject%' => 'Test',
+            '%to'      => '@outlook.com',
+            'from'     => 'me@outlook.com',
+            'sent>='   => '2023-10-01'
+        ];
+
+        $this->expectException('DomainException');
+        $messages = $google->getMessages('Inbox', $search, 25);
+    }
+
+    public function testGetMessages3()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $search = [
+            'subject'   => 'Test',
+            'to!='      => 'me@outlook.com',
+            'sent>'     => '2023-10-01',
+            'received<' => '2023-10-01',
+            'date<='    => '2023-10-01',
+            'unread'    => true
+        ];
+
+        $this->expectException('DomainException');
+        $messages = $google->getMessages('Inbox', $search, 25);
+    }
+
+    public function testGetMessage()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $message = $google->getMessage('123456789');
+    }
+
+    public function testGetMessageRaw()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $message = $google->getMessage('123456789', true);
+    }
+
+    public function testGetAttachments()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $attachments = $google->getAttachments('123456789');
+    }
+
+    public function testGetAttachment()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $attachment = $google->getAttachment('123456789', '123456789');
+    }
+
+    public function testMarkAsRead()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $google->markAsRead('123456789');
+    }
+
+    public function testMarkAsUnread()
+    {
+        $google = new Client\Google();
+        $google->createClient(__DIR__ . '/../tmp/my-google-app.json', 'test@gmail.com');
+        $google->setToken('AUTH_TOKEN');
+        $google->setTokenExpires(time() + 1000);
+
+        $this->expectException('DomainException');
+        $google->markAsUnread('123456789');
+    }
+
+    public function testGetMessagesException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $google = new Client\Google();
+        $messages = $google->getMessages();
+    }
+
+    public function testGetMessageException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $google = new Client\Google();
+        $message = $google->getMessage('123456789');
+    }
+
+    public function testGetAttachmentsException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $google = new Client\Google();
+        $message = $google->getAttachments('123456789');
+    }
+
+    public function testGetAttachmentException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $google = new Client\Google();
+        $message = $google->getAttachment('123456789', '123456798');
+    }
+
+    public function testMarkAsReadException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $google = new Client\Google();
+        $google->markAsRead('123456789');
+    }
+
+}
\ No newline at end of file
diff --git a/tests/Client/Office365Test.php b/tests/Client/Office365Test.php
new file mode 100644
index 0000000..a6cef6f
--- /dev/null
+++ b/tests/Client/Office365Test.php
@@ -0,0 +1,192 @@
+<?php
+
+namespace Pop\Mail\Test\Client;
+
+use Pop\Http;
+use Pop\Mail\Client;
+use PHPUnit\Framework\TestCase;
+
+class Office365Test extends TestCase
+{
+
+    public function testGetMessages1()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertTrue(is_array($office365->getMessages()));
+    }
+
+    public function testGetMessages2()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $search = [
+            'subject%' => 'Test',
+            '%to'      => '@outlook.com',
+            'from'     => 'me@outlook.com',
+            'sent>='   => '2023-10-01'
+        ];
+
+        $this->assertTrue(is_array($office365->getMessages('Inbox', $search, 25)));
+    }
+
+    public function testGetMessages3()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $search = [
+            'subject'   => 'Test',
+            'to!='      => 'me@outlook.com',
+            'sent>'     => '2023-10-01',
+            'received<' => '2023-10-01',
+            'date<='    => '2023-10-01',
+            'unread'    => true
+        ];
+
+        $this->assertTrue(is_array($office365->getMessages('Inbox', $search, 25)));
+    }
+
+    public function testGetMessage()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertTrue(is_array($office365->getMessage('123456789')));
+    }
+
+    public function testGetMessageRaw()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertTrue(is_array($office365->getMessage('123456789', true)));
+    }
+
+    public function testGetAttachments()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertTrue(is_array($office365->getAttachments('123456789')));
+    }
+
+    public function testGetAttachment()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertTrue(is_array($office365->getAttachment('123456789', '123456789')));
+    }
+
+    public function testMarkAsRead()
+    {
+        $office365 = new Client\Office365();
+        $office365->createClient(json_encode([
+            'client_id'     => 'CLIENT_ID',
+            'client_secret' => 'CLIENT_SECRET',
+            'scope'         => 'https://graph.microsoft.com/.default',
+            'tenant_id'     => 'TENANT_ID',
+            'account_id'    => 'ACCOUNT_ID',
+        ]));
+        $office365->setToken('AUTH_TOKEN');
+        $office365->setTokenExpires(time() + 1000);
+
+        $this->assertInstanceOf('Pop\Mail\Client\Office365', $office365->markAsRead('123456789'));
+        $this->assertInstanceOf('Pop\Mail\Client\Office365', $office365->markAsUnread('123456789'));
+    }
+
+    public function testGetMessagesException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $office365 = new Client\Office365();
+        $messages = $office365->getMessages();
+    }
+
+    public function testGetMessageException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $office365 = new Client\Office365();
+        $message = $office365->getMessage('123456789');
+    }
+
+    public function testGetAttachmentsException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $office365 = new Client\Office365();
+        $message = $office365->getAttachments('123456789');
+    }
+
+    public function testGetAttachmentException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $office365 = new Client\Office365();
+        $message = $office365->getAttachment('123456789', '123456798');
+    }
+
+    public function testMarkAsReadException()
+    {
+        $this->expectException('Pop\Mail\Client\Exception');
+        $office365 = new Client\Office365();
+        $office365->markAsRead('123456789');
+    }
+
+}
\ No newline at end of file