diff --git a/gtsam/navigation/MagFactor.h b/gtsam/navigation/MagFactor.h
index 82b120fab..b88d72725 100644
--- a/gtsam/navigation/MagFactor.h
+++ b/gtsam/navigation/MagFactor.h
@@ -21,8 +21,7 @@
 #include <gtsam/base/LieVector.h>
 #include <gtsam/base/LieScalar.h>
 
-using namespace std;
-using namespace gtsam;
+namespace gtsam {
 
 /**
  * Factor to calibrate local Earth magnetic field as well as magnetometer bias
@@ -119,3 +118,5 @@ public:
   }
 };
 
+}
+