diff --git a/tests/Admin/AdminTest.php b/tests/Admin/AdminTest.php
new file mode 100644
index 0000000..afb74f1
--- /dev/null
+++ b/tests/Admin/AdminTest.php
@@ -0,0 +1,26 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\tests\Calendar\Admin;
+
+/**
+ * @internal
+ */
+class AdminTest extends \PHPUnit\Framework\TestCase
+{
+    protected const MODULE_NAME = 'Calendar';
+    protected const URI_LOAD = 'http://127.0.0.1/en/backend/calendar';
+
+    use \Modules\tests\ModuleTestTrait;
+}
diff --git a/tests/Models/CalendarMapperTest.php b/tests/Models/CalendarMapperTest.php
new file mode 100644
index 0000000..0d199ae
--- /dev/null
+++ b/tests/Models/CalendarMapperTest.php
@@ -0,0 +1,62 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\tests\Calendar\Models;
+
+use Modules\Admin\Models\NullAccount;
+use Modules\Calendar\Models\Calendar;
+use Modules\Calendar\Models\CalendarMapper;
+use Modules\Calendar\Models\Event;
+
+/**
+ * @internal
+ */
+class CalendarMapperTest extends \PHPUnit\Framework\TestCase
+{
+    public function testCRUD() : void
+    {
+        $calendar = new Calendar();
+
+        $calendar->setName('Title');
+        $calendar->setDescription('Description');
+
+        $calendarEvent1 = new Event();
+        $calendarEvent1->setName('Running test');
+        $calendarEvent1->setDescription('Desc1');
+        $calendarEvent1->setCreatedBy(new NullAccount(1));
+        $calendarEvent1->getSchedule()->setCreatedBy(new NullAccount(1));
+        $calendar->addEvent($calendarEvent1);
+
+        $calendarEvent2 = new Event();
+        $calendarEvent2->setName('Running test2');
+        $calendarEvent2->setDescription('Desc2');
+        $calendarEvent2->setCreatedBy(new NullAccount(1));
+        $calendarEvent2->getSchedule()->setCreatedBy(new NullAccount(1));
+        $calendar->addEvent($calendarEvent2);
+
+        $id = CalendarMapper::create($calendar);
+        self::assertGreaterThan(0, $calendar->getId());
+        self::assertEquals($id, $calendar->getId());
+
+        $calendarR = CalendarMapper::get($calendar->getId());
+        self::assertEquals($calendar->getCreatedAt()->format('Y-m-d'), $calendarR->getCreatedAt()->format('Y-m-d'));
+        self::assertEquals($calendar->getDescription(), $calendarR->getDescription());
+        self::assertEquals($calendar->getName(), $calendarR->getName());
+
+        $expected = $calendar->getEvents();
+        $actual   = $calendarR->getEvents();
+
+        self::assertEquals(\end($expected)->getDescription(), \end($actual)->getDescription());
+    }
+}
diff --git a/tests/Models/CalendarTest.php b/tests/Models/CalendarTest.php
new file mode 100644
index 0000000..176c5e5
--- /dev/null
+++ b/tests/Models/CalendarTest.php
@@ -0,0 +1,68 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\tests\Calendar\Models;
+
+use Modules\Calendar\Models\Calendar;
+use Modules\Calendar\Models\Event;
+
+/**
+ * @internal
+ */
+class CalendarTest extends \PHPUnit\Framework\TestCase
+{
+    public function testDefault() : void
+    {
+        $calendar = new Calendar();
+
+        self::assertEquals(0, $calendar->getId());
+        self::assertEquals('', $calendar->getName());
+        self::assertEquals((new \DateTime('now'))->format('Y-m-d'), $calendar->getCreatedAt()->format('Y-m-d'));
+        self::assertEquals((new \DateTime('now'))->format('Y-m-d'), $calendar->getDate()->format('Y-m-d'));
+        self::assertEquals('', $calendar->getDescription());
+        self::assertEquals([], $calendar->getEvents());
+        self::assertInstanceOf('\Modules\Calendar\Models\NullEvent', $calendar->getEvent(0));
+        self::assertFalse($calendar->hasEventOnDate(new \DateTime('now')));
+        self::assertEquals([], $calendar->getEventByDate(new \DateTime('now')));
+    }
+
+    public function testSetGet() : void
+    {
+        $calendar = new Calendar();
+
+        $calendar->setDate($date = new \DateTime('2000-05-05'));
+        self::assertEquals($date->format('Y-m-d'), $calendar->getDate()->format('Y-m-d'));
+
+        $calendar->setName('Title');
+        self::assertEquals('Title', $calendar->getName());
+
+        $calendar->setDescription('Description');
+        self::assertEquals('Description', $calendar->getDescription());
+
+        $id      = [];
+        $id[]    = $calendar->addEvent(new Event());
+        $id[]    = $calendar->addEvent(new Event());
+        $success = $calendar->removeEvent(99);
+
+        self::assertFalse($success);
+
+        $success = $calendar->removeEvent($id[1]);
+        self::assertTrue($success);
+
+        self::assertEquals(0, $calendar->getEvents()[0]->getId());
+        self::assertEquals(0, $calendar->getEvent(0)->getId());
+
+        self::assertInstanceOf('\Modules\Calendar\Models\Event', $calendar->getEvent(1));
+    }
+}
diff --git a/tests/Models/EventMapperTest.php b/tests/Models/EventMapperTest.php
new file mode 100644
index 0000000..dc1c966
--- /dev/null
+++ b/tests/Models/EventMapperTest.php
@@ -0,0 +1,44 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\tests\Calendar\Models;
+
+use Modules\Admin\Models\NullAccount;
+use Modules\Calendar\Models\Event;
+use Modules\Calendar\Models\EventMapper;
+
+/**
+ * @internal
+ */
+class EventMapperTest extends \PHPUnit\Framework\TestCase
+{
+    public function testCRUD() : void
+    {
+        $calendarEvent1 = new Event();
+
+        $calendarEvent1->setName('Running test');
+        $calendarEvent1->setDescription('Desc1');
+        $calendarEvent1->setCreatedBy(new NullAccount(1));
+        $calendarEvent1->getSchedule()->setCreatedBy(new NullAccount(1));
+        $calendarEvent1->setCalendar(1);
+
+        $id = EventMapper::create($calendarEvent1);
+        self::assertGreaterThan(0, $calendarEvent1->getId());
+        self::assertEquals($id, $calendarEvent1->getId());
+
+        $eventR = EventMapper::get($calendarEvent1->getId());
+        self::assertEquals($calendarEvent1->getCreatedBy()->getId(), $eventR->getCreatedBy()->getId());
+        self::assertEquals($calendarEvent1->getDescription(), $eventR->getDescription());
+    }
+}
diff --git a/tests/Models/EventTest.php b/tests/Models/EventTest.php
new file mode 100644
index 0000000..947ac9f
--- /dev/null
+++ b/tests/Models/EventTest.php
@@ -0,0 +1,62 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\tests\Calendar\Models;
+
+use Modules\Admin\Models\NullAccount;
+use Modules\Calendar\Models\Event;
+use phpOMS\Account\Account;
+
+/**
+ * @internal
+ */
+class EventTest extends \PHPUnit\Framework\TestCase
+{
+    public function testDefault() : void
+    {
+        $event = new Event();
+
+        self::assertEquals(0, $event->getId());
+        self::assertEquals(0, $event->getCreatedBy()->getId());
+        self::assertEquals('', $event->getName());
+        self::assertEquals((new \DateTime('now'))->format('Y-m-d'), $event->getCreatedAt()->format('Y-m-d'));
+        self::assertEquals('', $event->getDescription());
+        self::assertEquals([], $event->getPeople());
+        self::assertInstanceOf('\Modules\Admin\Models\NullAccount', $event->getPerson(1));
+        self::assertInstanceOf('\phpOMS\Stdlib\Base\Location', $event->getLocation());
+    }
+
+    public function testSetGet() : void
+    {
+        $event = new Event();
+
+        $event->setCreatedBy(new NullAccount(1));
+        self::assertEquals(1, $event->getCreatedBy()->getId());
+
+        $event->setName('Name');
+        self::assertEquals('Name', $event->getName());
+
+        $event->setDescription('Description');
+        self::assertEquals('Description', $event->getDescription());
+
+        $event->addPerson(new Account());
+        $event->addPerson(new Account());
+        $success = $event->removePerson(99);
+
+        self::assertFalse($success);
+
+        $success = $event->removePerson(0);
+        self::assertTrue($success);
+    }
+}