Hello Jon Barron,
You can read the Getting Started section from RadContextMenu online help from here:
http://www.telerik.com/help/silverlight/contextmenu-getting-started.html
At the relevant part is that you have to use the RadContextMenu.ContextMenu attached property to attach context menu on a UIElement:
Let us know if you need more help.
Regards,
Hristo
the Telerik team
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