diff --git a/Demo_Design_Pattern_Persistent_Window.py b/Demo_Design_Pattern_Persistent_Window.py
new file mode 100644
index 00000000..cf8f3d21
--- /dev/null
+++ b/Demo_Design_Pattern_Persistent_Window.py
@@ -0,0 +1,23 @@
+# -------------------------------------#
+# DESIGN PATTERN 2 - Persistent Window #
+# Update a text field based on input   #
+# -------------------------------------#
+import sys
+if sys.version_info[0] >= 3:
+    import PySimpleGUI as sg
+else:
+    import PySimpleGUI27 as sg
+
+layout = [[sg.Text('Your typed chars appear here:'), sg.Text('', key='_OUTPUT_') ],
+          [sg.Input(key='_IN_')],
+          [sg.Button('Show'), sg.Button('Exit')],
+          ]
+
+window = sg.Window('My new window').Layout(layout)
+
+while True:                 # Event Loop
+    event, values = window.Read()
+    if event is None or event == 'Exit':
+        break
+    if event == 'Show':     # change the text "output" element to be the value of "input" element
+        window.FindElement('_OUTPUT_').Update(values['_IN_'])