diff --git a/etk/math/Transform3D.cpp b/etk/math/Transform3D.cpp
index 440e6de..8a84919 100644
--- a/etk/math/Transform3D.cpp
+++ b/etk/math/Transform3D.cpp
@@ -34,4 +34,8 @@ etk::Transform3D etk::Transform3D::identity() {
 	return etk::Transform3D(vec3(0.0, 0.0, 0.0), Quaternion::identity());
 }
 
+etk::Stream& etk::operator <<(etk::Stream& _os, const etk::Transform3D& _obj) {
+	_os << "transform3D(" << _obj.getPosition() << ";" << _obj.getOrientation() << ")";
+	return _os;
+}
 
diff --git a/etk/math/Transform3D.hpp b/etk/math/Transform3D.hpp
index 72f7e66..341a4da 100644
--- a/etk/math/Transform3D.hpp
+++ b/etk/math/Transform3D.hpp
@@ -124,6 +124,8 @@ namespace etk {
 				return *this;
 			}
 	};
+	//! @not_in_doc
+	etk::Stream& operator <<(etk::Stream& _os, const etk::Transform3D& _obj);
 }