Please, refer to the Nedyalkov's blog post about using RadDocking with PRISM
Also, there is a lot threads about this scenario and you can find a lot of information (including running sample) in our forums, but maybe the most completed thread is this one
Nevertheless the thread is from the forum thread, but your question is about WPF, the code is the same for both platforms.
Hope this helps.
the Telerik team
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