diff --git a/include/core/dbus/asio/executor.h b/include/core/dbus/asio/executor.h
index d1f043e..505a55b 100644
--- a/include/core/dbus/asio/executor.h
+++ b/include/core/dbus/asio/executor.h
@@ -18,18 +18,12 @@
 #ifndef CORE_DBUS_ASIO_EXECUTOR_H_
 #define CORE_DBUS_ASIO_EXECUTOR_H_
 
+#include <boost/asio/io_service.hpp>
+
 #include <core/dbus/bus.h>
 #include <core/dbus/executor.h>
 #include <core/dbus/visibility.h>
 
-namespace boost
-{
-namespace asio
-{
-class io_service;
-}
-}
-
 namespace core
 {
 namespace dbus