diff --git a/src/core/delete.c b/src/core/delete.c
index 9cfa71534..b86dcf304 100644
--- a/src/core/delete.c
+++ b/src/core/delete.c
@@ -261,8 +261,7 @@ meta_window_present_delete_dialog (MetaWindow *window, guint32 timestamp)
         {
           MetaWindow *w = tmp->data;
 
-          if (w->xtransient_for == window->xwindow &&
-              w->res_class &&
+          if (w->transient_for == window && w->res_class &&
               g_ascii_strcasecmp (w->res_class, "mutter-dialog") == 0)
             {
               meta_window_activate (w, timestamp);
diff --git a/src/core/place.c b/src/core/place.c
index 8894114d6..613f27061 100644
--- a/src/core/place.c
+++ b/src/core/place.c
@@ -610,7 +610,7 @@ meta_window_place (MetaWindow        *window,
   meta_topic (META_DEBUG_PLACEMENT, "Placing window %s\n", window->desc);
 
   windows = NULL;
-  
+
   switch (window->type)
     {
       /* Run placement algorithm on these. */
@@ -638,7 +638,7 @@ meta_window_place (MetaWindow        *window,
     case META_WINDOW_OVERRIDE_OTHER:
       goto done_no_constraints;
     }
-  
+
   if (meta_prefs_get_disable_workarounds ())
     {
       switch (window->type)
@@ -699,18 +699,11 @@ meta_window_place (MetaWindow        *window,
           goto done_no_constraints;
         }
     }
-  
-  if ((window->type == META_WINDOW_DIALOG ||
-       window->type == META_WINDOW_MODAL_DIALOG) &&
-      window->xtransient_for != None)
-    {
-      /* Center horizontally, at top of parent vertically */
 
-      MetaWindow *parent;
-          
-      parent =
-        meta_display_lookup_x_window (window->display,
-                                      window->xtransient_for);
+  if (window->type == META_WINDOW_DIALOG ||
+      window->type == META_WINDOW_MODAL_DIALOG)
+    {
+      MetaWindow *parent = meta_window_get_transient_for (window);
 
       if (parent)
         {
diff --git a/src/core/stack.c b/src/core/stack.c
index 4a3481120..c9223ccd4 100644
--- a/src/core/stack.c
+++ b/src/core/stack.c
@@ -1746,8 +1746,7 @@ get_default_focus_window (MetaStack     *stack,
       if (not_this_one != NULL)
         {
           if (transient_parent == NULL &&
-              not_this_one->xtransient_for != None &&
-              not_this_one->xtransient_for == window->xwindow)
+              meta_window_get_transient_for (not_this_one) == window)
             transient_parent = window;
 
           if (topmost_in_group == NULL &&