diff --git a/src/libslic3r/Geometry.cpp b/src/libslic3r/Geometry.cpp
index 441825654..f7f6bb2f9 100644
--- a/src/libslic3r/Geometry.cpp
+++ b/src/libslic3r/Geometry.cpp
@@ -728,7 +728,7 @@ void Transformation::reset_skew()
 
     const double average_scale = std::cbrt(scale(0, 0) * scale(1, 1) * scale(2, 2));
 
-    scale(0, 0) = average_scale;
+    scale(0, 0) = is_left_handed() ? -average_scale : average_scale;
     scale(1, 1) = average_scale;
     scale(2, 2) = average_scale;
 
diff --git a/src/slic3r/GUI/GUI_ObjectManipulation.cpp b/src/slic3r/GUI/GUI_ObjectManipulation.cpp
index d737a7be4..103198ca8 100644
--- a/src/slic3r/GUI/GUI_ObjectManipulation.cpp
+++ b/src/slic3r/GUI/GUI_ObjectManipulation.cpp
@@ -235,7 +235,11 @@ ObjectManipulation::ObjectManipulation(wxWindow* parent) :
 
     add_label(&m_scale_Label,   L("Scale"), v_sizer);
     wxStaticText* size_Label {nullptr};
-    add_label(&size_Label,      L("Size"), v_sizer);
+#if ENABLE_WORLD_COORDINATE
+    add_label(&size_Label, L("Size [World]"), v_sizer);
+#else
+    add_label(&size_Label, L("Size"), v_sizer);
+#endif // ENABLE_WORLD_COORDINATE
     if (wxOSX) set_font_and_background_style(size_Label, wxGetApp().normal_font());
 
     sizer->Add(v_sizer, 0, wxLEFT, border);
@@ -479,11 +483,18 @@ ObjectManipulation::ObjectManipulation(wxWindow* parent) :
 #if ENABLE_WORLD_COORDINATE
         GLCanvas3D* canvas = wxGetApp().plater()->canvas3D();
         Selection& selection = canvas->get_selection();
-        if (selection.is_single_volume_or_modifier())
+        if (selection.is_single_volume_or_modifier()) {
+            const bool is_left_handed = selection.get_first_volume()->get_volume_transformation().is_left_handed();
             const_cast<GLVolume*>(selection.get_first_volume())->set_volume_scaling_factor(Vec3d::Ones());
+            if (is_left_handed)
+                const_cast<GLVolume*>(selection.get_first_volume())->set_volume_mirror({ -1.0 , 1.0, 1.0 });
+        }
         else if (selection.is_single_full_instance()) {
+            const bool is_left_handed = selection.get_first_volume()->get_instance_transformation().is_left_handed();
             for (unsigned int idx : selection.get_volume_idxs()) {
                 const_cast<GLVolume*>(selection.get_volume(idx))->set_instance_scaling_factor(Vec3d::Ones());
+                if (is_left_handed)
+                    const_cast<GLVolume*>(selection.get_volume(idx))->set_instance_mirror({ -1.0 , 1.0, 1.0 });
             }
         }
         else
@@ -712,21 +723,21 @@ void ObjectManipulation::update_settings_value(const Selection& selection)
 #if ENABLE_WORLD_COORDINATE
         if (is_world_coordinates()) {
             m_new_position = volume->get_instance_offset();
-            m_new_scale_label_string = L("Scale");
-            m_new_scale = Vec3d(100.0, 100.0, 100.0);
             m_new_size = selection.get_bounding_box_in_current_reference_system().first.size();
+            m_new_scale = m_new_size.cwiseQuotient(selection.get_unscaled_instance_bounding_box().size()) * 100.0;
+            m_new_rotate_label_string = L("Rotate (relative)");
 #else
         if (m_world_coordinates) {
             m_new_scale    = m_new_size.cwiseQuotient(selection.get_unscaled_instance_bounding_box().size()) * 100.0;
             m_new_size = selection.get_scaled_instance_bounding_box().size();
-#endif // ENABLE_WORLD_COORDINATE
             m_new_rotate_label_string = L("Rotate");
+#endif // ENABLE_WORLD_COORDINATE
             m_new_rotation = Vec3d::Zero();
         }
         else {
 #if ENABLE_WORLD_COORDINATE
-            m_new_move_label_string = L("Translate");
-            m_new_rotate_label_string = L("Rotate");
+            m_new_move_label_string = L("Translate (relative) [World]");
+            m_new_rotate_label_string = L("Rotate (relative)");
             m_new_position = Vec3d::Zero();
             m_new_rotation = Vec3d::Zero();
             m_new_scale = Vec3d(100.0, 100.0, 100.0);
@@ -768,15 +779,15 @@ void ObjectManipulation::update_settings_value(const Selection& selection)
             const Vec3d& offset = trafo.get_offset();
 
             m_new_position = offset;
-            m_new_rotate_label_string = L("Rotate");
+            m_new_rotate_label_string = L("Rotate (relative)");
             m_new_scale_label_string = L("Scale");
             m_new_scale = Vec3d(100.0, 100.0, 100.0);
             m_new_rotation = Vec3d::Zero();
             m_new_size = selection.get_bounding_box_in_current_reference_system().first.size();
         }
         else if (is_local_coordinates()) {
-            m_new_move_label_string = L("Translate");
-            m_new_rotate_label_string = L("Rotate");
+            m_new_move_label_string = L("Translate (relative) [World]");
+            m_new_rotate_label_string = L("Rotate (relative)");
             m_new_position = Vec3d::Zero();
             m_new_rotation = Vec3d::Zero();
             m_new_scale = volume->get_volume_scaling_factor() * 100.0;
@@ -785,7 +796,11 @@ void ObjectManipulation::update_settings_value(const Selection& selection)
         else {
 #endif // ENABLE_WORLD_COORDINATE
             m_new_position = volume->get_volume_offset();
+#if ENABLE_WORLD_COORDINATE
+            m_new_rotate_label_string = L("Rotate (relative)");
+#else
             m_new_rotate_label_string = L("Rotate");
+#endif // ENABLE_WORLD_COORDINATE
             m_new_rotation = Vec3d::Zero();
 #if ENABLE_WORLD_COORDINATE
             m_new_scale_label_string = L("Scale");
@@ -1221,10 +1236,8 @@ void ObjectManipulation::change_scale_value(int axis, double value)
         scale = scale.cwiseQuotient(ref_scale);
         ref_scale = Vec3d::Ones();
     }
-    else if (selection.is_single_full_instance()) {
-        scale = scale.cwiseQuotient(ref_scale);
-        ref_scale = Vec3d::Ones();
-    }
+    else if (selection.is_single_full_instance())
+        ref_scale = 100.0 * Vec3d::Ones();
 
     this->do_scale(axis, scale.cwiseQuotient(ref_scale));
 #else
@@ -1276,9 +1289,9 @@ void ObjectManipulation::change_size_value(int axis, double value)
     else if (selection.is_single_full_instance()) {
 #if ENABLE_WORLD_COORDINATE
         if (is_world_coordinates())
-            ref_size = selection.get_unscaled_instance_bounding_box().size();
-        size = size.cwiseQuotient(ref_size);
-        ref_size = Vec3d::Ones();
+            ref_size = selection.get_full_unscaled_instance_bounding_box().size();
+        else
+            ref_size = selection.get_full_unscaled_instance_local_bounding_box().size();
 #else
         ref_size = m_world_coordinates ?
             selection.get_unscaled_instance_bounding_box().size() :
@@ -1311,8 +1324,7 @@ void ObjectManipulation::do_scale(int axis, const Vec3d &scale) const
     else if (is_instance_coordinates())
         transformation_type.set_instance();
 
-    if (!(selection.is_single_volume_or_modifier() && is_local_coordinates()) &&
-        !(selection.is_single_full_instance() && is_instance_coordinates()))
+    if (selection.is_single_volume_or_modifier() && !is_local_coordinates())
         transformation_type.set_relative();
 
     const Vec3d scaling_factor = m_uniform_scale ? scale(axis) * Vec3d::Ones() : scale;
diff --git a/src/slic3r/GUI/Selection.cpp b/src/slic3r/GUI/Selection.cpp
index 5678008d3..072efc2d8 100644
--- a/src/slic3r/GUI/Selection.cpp
+++ b/src/slic3r/GUI/Selection.cpp
@@ -969,7 +969,7 @@ void Selection::translate(const Vec3d& displacement, TransformationType transfor
                 v.set_instance_offset(inst_trafo.get_offset() + inst_trafo.get_rotation_matrix() * displacement);
             }
             else
-                transform_instance_relative(v, volume_data, transformation_type, Geometry::translation_transform(displacement), m_cache.dragging_center);
+                transform_instance_relative_world(v, volume_data, transformation_type, Geometry::translation_transform(displacement), m_cache.dragging_center);
         }
         else {
             if (transformation_type.local() && transformation_type.absolute()) {
@@ -1066,7 +1066,7 @@ void Selection::rotate(const Vec3d& rotation, TransformationType transformation_
                 v.set_instance_transformation(Geometry::translation_transform(world_inst_pivot) * inst_trafo.get_offset_matrix() * trafo * Transform3d(inst_scale) * Geometry::translation_transform(-local_inst_pivot));
             }
             else
-                transform_instance_relative(v, volume_data, transformation_type, rotation_matrix, m_cache.dragging_center);
+                transform_instance_relative_world(v, volume_data, transformation_type, rotation_matrix, m_cache.dragging_center);
         }
         else {
             if (!is_single_volume_or_modifier()) {
@@ -1471,6 +1471,29 @@ void Selection::scale_and_translate(const Vec3d& scale, const Vec3d& translation
         const VolumeCache& volume_data = m_cache.volumes_data[i];
         const Geometry::Transformation& inst_trafo = volume_data.get_instance_transform();
 
+        Vec3d relative_scale = scale;
+
+        if (transformation_type.absolute()) {
+            if (m_mode == Instance) {
+                if (is_single_full_instance()) {
+                    BoundingBoxf3 current_box = m_box.get_bounding_box();
+                    BoundingBoxf3 original_box;
+                    if (transformation_type.world())
+                        original_box = get_full_unscaled_instance_bounding_box();
+                    else
+                        original_box = get_full_unscaled_instance_local_bounding_box();
+
+                    relative_scale = original_box.size().cwiseProduct(scale).cwiseQuotient(current_box.size());
+
+                    std::cout << to_string(scale) << to_string(original_box.size()) << to_string(current_box.size()) << to_string(relative_scale) << "\n";
+
+                    transformation_type.set_relative();
+                }
+            }
+            else {
+            }
+        }
+
         if (m_mode == Instance) {
             if (transformation_type.instance()) {
                 const Vec3d world_inst_pivot = m_cache.dragging_center - inst_trafo.get_offset();
@@ -1478,11 +1501,11 @@ void Selection::scale_and_translate(const Vec3d& scale, const Vec3d& translation
                 Matrix3d inst_rotation, inst_scale;
                 inst_trafo.get_matrix().computeRotationScaling(&inst_rotation, &inst_scale);
                 const Transform3d offset_trafo = Geometry::translation_transform(inst_trafo.get_offset() + inst_rotation * translation);
-                const Transform3d scale_trafo = Transform3d(inst_scale) * Geometry::scale_transform(scale);
+                const Transform3d scale_trafo = Transform3d(inst_scale) * Geometry::scale_transform(relative_scale);
                 v.set_instance_transformation(Geometry::translation_transform(world_inst_pivot) * offset_trafo * Transform3d(inst_rotation) * scale_trafo * Geometry::translation_transform(-local_inst_pivot));
             }
             else
-                transform_instance_relative(v, volume_data, transformation_type, Geometry::translation_transform(translation) * Geometry::scale_transform(scale), m_cache.dragging_center);
+                transform_instance_relative_world(v, volume_data, transformation_type, Geometry::translation_transform(translation) * Geometry::scale_transform(relative_scale), m_cache.dragging_center);
         }
         else {
             if (!is_single_volume_or_modifier()) {
@@ -1509,9 +1532,9 @@ void Selection::scale_and_translate(const Vec3d& scale, const Vec3d& translation
 
 #if !DISABLE_INSTANCES_SYNCH
     if (m_mode == Instance)
-      synchronize_unselected_instances(SyncRotationType::NONE);
+        synchronize_unselected_instances(SyncRotationType::NONE);
     else if (m_mode == Volume)
-      synchronize_unselected_volumes();
+        synchronize_unselected_volumes();
 #endif // !DISABLE_INSTANCES_SYNCH
 
     ensure_on_bed();
@@ -3297,7 +3320,7 @@ void Selection::paste_objects_from_clipboard()
 }
 
 #if ENABLE_WORLD_COORDINATE
-void Selection::transform_instance_relative(GLVolume& volume, const VolumeCache& volume_data, TransformationType transformation_type,
+void Selection::transform_instance_relative_world(GLVolume& volume, const VolumeCache& volume_data, TransformationType transformation_type,
     const Transform3d& transform, const Vec3d& world_pivot)
 {
     assert(transformation_type.relative());
diff --git a/src/slic3r/GUI/Selection.hpp b/src/slic3r/GUI/Selection.hpp
index 36f973839..29398eabf 100644
--- a/src/slic3r/GUI/Selection.hpp
+++ b/src/slic3r/GUI/Selection.hpp
@@ -514,7 +514,7 @@ private:
     void paste_objects_from_clipboard();
 
 #if ENABLE_WORLD_COORDINATE
-    void transform_instance_relative(GLVolume& volume, const VolumeCache& volume_data, TransformationType transformation_type,
+    void transform_instance_relative_world(GLVolume& volume, const VolumeCache& volume_data, TransformationType transformation_type,
         const Transform3d& transform, const Vec3d& world_pivot);
     void transform_volume_relative(GLVolume& volume, const VolumeCache& volume_data, TransformationType transformation_type,
         const Transform3d& transform, const Vec3d& world_pivot);