Sometimes I look at what people search for when they hit my blog and see some trending questions that don’t seem to have easily findable answers. This one seems to be related to how to set the limit for moving a GridSplitter… Well – you don’t actually touch the GridSplitter to do that. You need to modify your RowDefinition or ColumnDefinition. In a similar way that you can define MinWidth/MaxWidth/MinHeight/MaxHeight on any FrameworkElement – you can do MinWidth/MaxWidth on a ColumnDefinition and MinHeight/MaxHeight on a RowDefinition. By setting these – you limit how much the GridSplitter will be able to resize them. I actually take these into account in my SimpleGridSplitter implementation, so if you have lots of rows or columns in your WPF app – you can use that one. Silverlight works fine there with its own GridSplitter.