Modern users are cockered with well-designed fluid UIs. Based on our own experience we know what an wow effect can layout to layout transitions make for application. Unfortunately, by this time there were no free and open source solution to support them in WPF. Yuriy Zanichkovskyy has implemented an open-source library that for Layout-to-Layout transitions in WPF. You can find detailed description of the library on CodeProject and fork the code on GitHub.