I m not sure what precisely you re doing, but under normal circumstances, you should be able to resize your page without doing a page refresh, and hence, without losing state in your Silverlight controls. Are you doing something that s causing a page refresh? If so, yes, that would cause you to lose state. And if that s the case, and you really do need the round-trip back to the server, then you ll need to store your state somewhere else, for instance, in the ASPX page ViewState, or on a web service, or in your local Silverlight storage. But my guess is that you don t actually need the round-trip to the server, i.e., that it s being caused by a side-effect of something else you re doing. I d start there.