What's the correct pattern to resize controls when a font size changes? 

For example, I used the WPF designer to make a form, and placed UI elements from the toolbox. Late in the game I got the requirement that the font size of every UI element needs to be configurable, so now I'm thinking there has to be a better way to resize controls when the font size changes. Right now I'm doing alot of code behind calculations on Margin properties.