diff --git a/gtsam/geometry/StereoPoint2.cpp b/gtsam/geometry/StereoPoint2.cpp
index 4aaa513f5..cd6f09507 100644
--- a/gtsam/geometry/StereoPoint2.cpp
+++ b/gtsam/geometry/StereoPoint2.cpp
@@ -19,15 +19,18 @@
 #include <gtsam/geometry/StereoPoint2.h>
 
 using namespace std;
-using namespace gtsam;
+
+namespace gtsam {
 
 /* ************************************************************************* */
 void StereoPoint2::print(const string& s) const {
   cout << s << "(" << uL_ << ", " << uR_ << ", " << v_ << ")"  << endl;
 }
-/* ************************************************************************* */
 
+/* ************************************************************************* */
 ostream &operator<<(ostream &os, const StereoPoint2& p) {
-  os << '(' << p.uL() << ", " << p.uR() << p.v() << ')';
+  os << '(' << p.uL() << ", " << p.uR() << ", " << p.v() << ')';
   return os;
 }
+
+} // namespace gtsam