diff --git a/mtg-collector/gui.py b/mtg-collector/gui.py
index ce55b58..28df7c8 100644
--- a/mtg-collector/gui.py
+++ b/mtg-collector/gui.py
@@ -102,6 +102,14 @@ class MainWindow(Gtk.Window):
     def mb_save_lib(self, menu_item):
         util.save_library()
 
+    def do_delete_event(self, event):
+        if util.unsaved_changes:
+            response = util.show_question_dialog("Unsaved Changes", "You have unsaved changes in your library. "
+                                                                    "Save before exiting?")
+            if response == Gtk.ResponseType.YES:
+                util.save_library()
+
+
 win = MainWindow()
 win.connect('delete-event', Gtk.main_quit)
 GObject.threads_init()
diff --git a/mtg-collector/util.py b/mtg-collector/util.py
index 14353f8..295e3a1 100644
--- a/mtg-collector/util.py
+++ b/mtg-collector/util.py
@@ -99,6 +99,14 @@ def push_status(msg):
     status_bar.push(0, msg)
 
 
+def show_question_dialog(title, message):
+    dialog = Gtk.MessageDialog(window, 0, Gtk.MessageType.QUESTION,
+                               Gtk.ButtonsType.YES_NO, title)
+    dialog.format_secondary_text(message)
+    response = dialog.run()
+    dialog.destroy
+    return response
+
 def show_message(title, message):
     dialog = Gtk.MessageDialog(window, 0, Gtk.MessageType.INFO,
                                Gtk.ButtonsType.OK, title)