diff --git a/test/php/library/Director/Objects/IcingaTimePeriodTest.php b/test/php/library/Director/Objects/IcingaTimePeriodTest.php
index 2e70faeb..84496d32 100644
--- a/test/php/library/Director/Objects/IcingaTimePeriodTest.php
+++ b/test/php/library/Director/Objects/IcingaTimePeriodTest.php
@@ -9,6 +9,8 @@ class IcingaTimePeriodTest extends BaseTestCase
 {
     protected $testPeriodName = '___TEST___timeperiod';
 
+    protected $createdNames = [];
+
     public function testWhetherUpdatedTimeperiodsAreCorrectlyStored()
     {
         if ($this->skipForMissingDb()) {
@@ -54,12 +56,15 @@ class IcingaTimePeriodTest extends BaseTestCase
         );
     }
 
-    protected function createTestPeriod()
+    protected function createTestPeriod($suffix = '', $testRanges = [])
     {
         $db = $this->getDb();
+        $name = $this->testPeriodName . $suffix;
+
+        $this->createdNames[] = $name;
         $object = IcingaTimePeriod::create(
             array(
-                'object_name' => $this->testPeriodName,
+                'object_name' => $name,
                 'object_type' => 'object'
             ),
             $db
@@ -67,11 +72,13 @@ class IcingaTimePeriodTest extends BaseTestCase
         $object->store();
         $ranges = $object->ranges();
 
-        $testRanges = array(
-            'monday'    => '00:00-24:00',
-            'tuesday'   => '00:00-24:00',
-            'wednesday' => '00:00-24:00',
-        );
+        if (empty($testRanges)) {
+            $testRanges = array(
+                'monday'    => '00:00-24:00',
+                'tuesday'   => '00:00-24:00',
+                'wednesday' => '00:00-24:00',
+            );
+        }
 
         $ranges->set($testRanges);
         $object->store();
@@ -98,16 +105,80 @@ class IcingaTimePeriodTest extends BaseTestCase
         $this->assertFalse($period->isActive(strtotime('2016-05-19 10:00:00')));
     }
 
-    protected function loadTestPeriod()
+    public function testPeriodWithIncludes()
     {
-        return IcingaTimePeriod::load($this->testPeriodName, $this->getDb());
+        $period = $this->createTestPeriod();
+        $include = $this->createTestPeriod('include', ['thursday' => '00:00-24:00']);
+
+        $period->set('includes', $include->object_name);
+        $period->store();
+
+        // Wednesday:
+        $this->assertTrue($period->isActive(strtotime('2016-05-18 10:00:00')));
+        // Thursday:
+        $this->assertTrue($period->isActive(strtotime('2016-05-19 10:00:00')));
+    }
+
+    public function testPeriodWithExcludes()
+    {
+        $period = $this->createTestPeriod();
+        $exclude = $this->createTestPeriod('exclude', ['wednesday' => '00:00-24:00']);
+
+        $period->set('excludes', $exclude->object_name);
+        $period->store();
+
+        // Wednesday:
+        $this->assertFalse($period->isActive(strtotime('2016-05-18 10:00:00')));
+        // Thursday:
+        $this->assertFalse($period->isActive(strtotime('2016-05-19 10:00:00')));
+    }
+
+    public function testPeriodPreferingIncludes()
+    {
+        $period = $this->createTestPeriod();
+        $include = $this->createTestPeriod('include', ['thursday' => '00:00-24:00']);
+        $exclude = $this->createTestPeriod('exclude', ['thursday' => '00:00-24:00']);
+
+        $period->set('includes', $include->object_name);
+        $period->set('excludes', $exclude->object_name);
+        $period->store();
+
+        // Wednesday:
+        $this->assertTrue($period->isActive(strtotime('2016-05-18 10:00:00')));
+        // Thursday:
+        $this->assertTrue($period->isActive(strtotime('2016-05-19 10:00:00')));
+    }
+
+    public function testPeriodPreferingExcludes()
+    {
+        $period = $this->createTestPeriod();
+        $include = $this->createTestPeriod('include', ['thursday' => '00:00-24:00']);
+        $exclude = $this->createTestPeriod('exclude', ['thursday' => '00:00-24:00']);
+
+        $period->set('prefer_includes', false);
+        $period->set('includes', $include->object_name);
+        $period->set('excludes', $exclude->object_name);
+        $period->store();
+
+        // Wednesday:
+        $this->assertTrue($period->isActive(strtotime('2016-05-18 10:00:00')));
+        // Thursday:
+        $this->assertFalse($period->isActive(strtotime('2016-05-19 10:00:00')));
+    }
+
+    protected function loadTestPeriod($suffix = '')
+    {
+        return IcingaTimePeriod::load($this->testPeriodName . $suffix, $this->getDb());
     }
 
     public function tearDown()
     {
         $db = $this->getDb();
-        if (IcingaTimePeriod::exists($this->testPeriodName, $db)) {
-            IcingaTimePeriod::load($this->testPeriodName, $db)->delete();
+
+        foreach ($this->createdNames as $name) {
+            if (IcingaTimePeriod::exists($name, $db)) {
+                IcingaTimePeriod::load($name, $db)->delete();
+            }
         }
     }
 }