This is a two question. Is it possible to take advantage of the automatic client-side legalization with ASP.NET webform? If so, is there any example available? I think that xVal will be ASP.NET validation control. These controls will be equal to WebVorms & lt;% = Html.ClientSideValidation ()%> For MVC but before that I have a lot of depth Junk, I want to see if anyone has tried it. (And yes I tried, but the results were not very useful.) to: I think it should be optimized for XLL to work with ASP.NET webform. However, to keep the xVal project centered, I do not want to try to add that support nor would I like to make the MVC experience as streamlined as possible. Though feel free to go to yourself! -, xVal coordinator So when I have some time, I will see if I can not modify the xVal source to work with the webform . Update : I have created a CodePlex project for this. See for details.