diff --git a/Basic_viewer/doc/Basic_viewer/CGAL/Qt/Basic_viewer.h b/Basic_viewer/doc/Basic_viewer/CGAL/Qt/Basic_viewer.h
index adcdbbc266a..5ef340bd40d 100644
--- a/Basic_viewer/doc/Basic_viewer/CGAL/Qt/Basic_viewer.h
+++ b/Basic_viewer/doc/Basic_viewer/CGAL/Qt/Basic_viewer.h
@@ -1,10 +1,11 @@
 namespace CGAL {
+  namespace Qt {
 
 //------------------------------------------------------------------------------
 /*!
  \ingroup PkgBasicViewerClasses
 
-The class `Basic_viewer` is a Qt widget based on `QGLViewer` that allows to visualize 3D elements: points, segments, triangles, rays and lines. This class stores a reference to a `Graphics_scene`. Elements can either be added directly in the viewer or through the scene. This class requires `CGAL_Qt5`, and is only available if the macro `CGAL_USE_BASIC_VIEWER` is defined. Linking with the cmake target `CGAL::CGAL_Basic_viewer` will link with `CGAL_Qt5` and add the definition `CGAL_USE_BASIC_VIEWER`.
+The class `Basic_viewer` is a Qt widget based on `QGLViewer` that allows to visualize 3D elements: points, segments, triangles, rays and lines. This class stores a reference to a `Graphics_scene`. Elements are added through the scene. This class requires `CGAL_Qt5`, and is only available if the macro `CGAL_USE_BASIC_VIEWER` is defined. Linking with the cmake target `CGAL::CGAL_Basic_viewer` will link with `CGAL_Qt5` and add the definition `CGAL_USE_BASIC_VIEWER`.
 
 */
 class Basic_viewer : public CGAL::QGLViewer
@@ -132,7 +133,7 @@ public:
 
   /// Function called when a key is pressed. Users can define their own function in order
   /// to add specific behavior.
-  std::function<bool(QKeyEvent *, CGAL::Basic_viewer *)> on_key_pressed;
+  std::function<bool(QKeyEvent *, CGAL::Qt::Basic_viewer *)> on_key_pressed;
 };
 
 
@@ -157,6 +158,8 @@ public:
   Basic_viewer& basic_viewer();
 };
 
+} // End namespace Qt
+
 //------------------------------------------------------------------------------
 /*!
  \ingroup PkgBasicViewerClasses
diff --git a/Basic_viewer/include/CGAL/Qt/Basic_viewer.h b/Basic_viewer/include/CGAL/Qt/Basic_viewer.h
index acd9d8b66dd..60b16ff2b20 100644
--- a/Basic_viewer/include/CGAL/Qt/Basic_viewer.h
+++ b/Basic_viewer/include/CGAL/Qt/Basic_viewer.h
@@ -59,7 +59,7 @@
 #define CGAL_BASIC_VIEWER_INIT_SIZE_Y 450
 
 namespace CGAL {
-
+namespace Qt {
 //------------------------------------------------------------------------------
 class Basic_viewer : public CGAL::QGLViewer
 {
@@ -1457,7 +1457,7 @@ protected:
     return text;
   }
 public:
-  std::function<bool(QKeyEvent *, CGAL::Basic_viewer *)> on_key_pressed;
+  std::function<bool(QKeyEvent *, CGAL::Qt::Basic_viewer *)> on_key_pressed;
 
 protected:
   const Graphics_scene& gBuffer;
@@ -1537,30 +1537,6 @@ protected:
 
 };
 
-inline
-void draw_graphics_scene(const Graphics_scene& graphics_scene,
-                         const char *title="CGAL Basic Viewer")
-{
-#if defined(CGAL_TEST_SUITE)
-  bool cgal_test_suite = true;
-#else
-  bool cgal_test_suite = qEnvironmentVariableIsSet("CGAL_TEST_SUITE");
-#endif
-
-  if (!cgal_test_suite)
-  {
-    Qt::init_ogl_context(4, 3);
-
-    int argc = 1;
-    const char *argv[2] = {title, nullptr};
-    QApplication app(argc, const_cast<char **>(argv));
-    Basic_viewer basic_viewer(app.activeWindow(), graphics_scene, title);
-
-    basic_viewer.show();
-    app.exec();
-  }
-}
-
 //------------------------------------------------------------------------------
 class QApplication_and_basic_viewer
 {
@@ -1622,6 +1598,36 @@ protected:
   int m_argc;
 };
 
+} // End namespace Qt
+
+// A shortcut to use directly CGAL::Basic_viewer instead of CGAL::Qt::Basic_viewer.
+// Can be changed later if we have several viewers.
+using Qt::Basic_viewer;
+
+inline
+void draw_graphics_scene(const Graphics_scene& graphics_scene,
+                         const char *title="CGAL Basic Viewer")
+{
+#if defined(CGAL_TEST_SUITE)
+  bool cgal_test_suite = true;
+#else
+  bool cgal_test_suite = qEnvironmentVariableIsSet("CGAL_TEST_SUITE");
+#endif
+
+  if (!cgal_test_suite)
+  {
+    Qt::init_ogl_context(4, 3);
+
+    int argc = 1;
+    const char *argv[2] = {title, nullptr};
+    QApplication app(argc, const_cast<char **>(argv));
+    Basic_viewer basic_viewer(app.activeWindow(), graphics_scene, title);
+
+    basic_viewer.show();
+    app.exec();
+  }
+}
+
 } // End namespace CGAL
 
 #else // CGAL_USE_BASIC_VIEWER