Thanks Robert, I have seen that property. But I can't seem to figure out how to work with it. It doesn't actually tell you the active widget until a user starts clicking on the map to measure. There are no events on the measurement widget and I'm not sure how to set a listener on the activeWidget property. The only thing I can think of is to use the 'click' event to check the activeWidget and then change the unitOptions. But that seems a little heavy handed every time a user clicks on the map. Is there an easy way to listen for changes to the activeWidget?