You can't open a Template as a popup, Phil is correct, you can only open Windows in a client. Consider Templates as components, just like a Label. A Template is dragged onto a Window or into another Template, and what is created is actually a Template container which uses a path property (templatePath? I think is the name, it's been a while since I've used Vision) to tell it which Template to display. What you can do though, is make this template path dynamic to display different Templates based on conditions