diff --git a/test/dbus_passive_unittest.cpp b/test/dbus_passive_unittest.cpp
index d4e9e98..5bddf51 100644
--- a/test/dbus_passive_unittest.cpp
+++ b/test/dbus_passive_unittest.cpp
@@ -11,6 +11,11 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+namespace pid_control
+{
+namespace
+{
+
 using ::testing::_;
 using ::testing::InSequence;
 using ::testing::Invoke;
@@ -529,3 +534,6 @@
     EXPECT_DOUBLE_EQ(0, passive->getMin());
     EXPECT_DOUBLE_EQ(0, passive->getMax());
 }
+
+} // namespace
+} // namespace pid_control