diff --git a/lib/base/defer.hpp b/lib/base/defer.hpp
new file mode 100644
index 000000000..05ae0b819
--- /dev/null
+++ b/lib/base/defer.hpp
@@ -0,0 +1,59 @@
+/******************************************************************************
+ * Icinga 2                                                                   *
+ * Copyright (C) 2012-2018 Icinga Development Team (https://icinga.com/)      *
+ *                                                                            *
+ * This program is free software; you can redistribute it and/or              *
+ * modify it under the terms of the GNU General Public License                *
+ * as published by the Free Software Foundation; either version 2             *
+ * of the License, or (at your option) any later version.                     *
+ *                                                                            *
+ * 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 General Public License for more details.                               *
+ *                                                                            *
+ * You should have received a copy of the GNU General Public License          *
+ * along with this program; if not, write to the Free Software Foundation     *
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
+ ******************************************************************************/
+
+#ifndef DEFER
+#define DEFER
+
+#include <functional>
+#include <utility>
+
+namespace icinga
+{
+
+/**
+ * An action to be executed at end of scope.
+ *
+ * @ingroup base
+ */
+class Defer
+{
+public:
+	inline
+	Defer(std::function<void()> func) : m_Func(std::move(func))
+	{
+	}
+
+	Defer(const Defer&) = delete;
+	Defer(Defer&&) = delete;
+	Defer& operator=(const Defer&) = delete;
+	Defer& operator=(Defer&&) = delete;
+
+	inline
+	~Defer()
+	{
+		m_Func();
+	}
+
+private:
+	std::function<void()> m_Func;
+};
+
+}
+
+#endif /* DEFER */
diff --git a/lib/checker/checkercomponent.cpp b/lib/checker/checkercomponent.cpp
index c14259b88..8878a9d29 100644
--- a/lib/checker/checkercomponent.cpp
+++ b/lib/checker/checkercomponent.cpp
@@ -23,6 +23,7 @@
 #include "icinga/cib.hpp"
 #include "remote/apilistener.hpp"
 #include "base/configtype.hpp"
+#include "base/defer.hpp"
 #include "base/objectlock.hpp"
 #include "base/utility.hpp"
 #include "base/perfdatavalue.hpp"
@@ -73,6 +74,7 @@ void CheckerComponent::Start(bool runtimeCreated)
 	Log(LogInformation, "CheckerComponent")
 		<< "'" << GetName() << "' started.";
 
+	m_RunningChecks.store(0);
 
 	m_Thread = std::thread(std::bind(&CheckerComponent::CheckThreadProc, this));
 
@@ -93,6 +95,10 @@ void CheckerComponent::Stop(bool runtimeRemoved)
 	m_ResultTimer->Stop();
 	m_Thread.join();
 
+	while (m_RunningChecks.load()) {
+		Utility::Sleep(1.0 / 60.0);
+	}
+
 	Log(LogInformation, "CheckerComponent")
 		<< "'" << GetName() << "' stopped.";
 
@@ -207,6 +213,8 @@ void CheckerComponent::CheckThreadProc()
 
 		Checkable::IncreasePendingChecks();
 
+		m_RunningChecks.fetch_add(1);
+
 		Utility::QueueAsyncCallback(std::bind(&CheckerComponent::ExecuteCheckHelper, CheckerComponent::Ptr(this), checkable));
 
 		lock.lock();
@@ -215,6 +223,10 @@ void CheckerComponent::CheckThreadProc()
 
 void CheckerComponent::ExecuteCheckHelper(const Checkable::Ptr& checkable)
 {
+	Defer decrementRunningChecks ([this]{
+		m_RunningChecks.fetch_sub(1);
+	});
+
 	try {
 		checkable->ExecuteCheck();
 	} catch (const std::exception& ex) {
diff --git a/lib/checker/checkercomponent.hpp b/lib/checker/checkercomponent.hpp
index f69f5092e..3c2753973 100644
--- a/lib/checker/checkercomponent.hpp
+++ b/lib/checker/checkercomponent.hpp
@@ -25,11 +25,13 @@
 #include "base/configobject.hpp"
 #include "base/timer.hpp"
 #include "base/utility.hpp"
+#include <atomic>
 #include <boost/thread/mutex.hpp>
 #include <boost/thread/condition_variable.hpp>
 #include <boost/multi_index_container.hpp>
 #include <boost/multi_index/ordered_index.hpp>
 #include <boost/multi_index/key_extractors.hpp>
+#include <cstdint>
 #include <thread>
 
 namespace icinga
@@ -90,6 +92,7 @@ private:
 	boost::condition_variable m_CV;
 	bool m_Stopped{false};
 	std::thread m_Thread;
+	std::atomic<uintmax_t> m_RunningChecks;
 
 	CheckableSet m_IdleCheckables;
 	CheckableSet m_PendingCheckables;