If you put down an inch or so of the clumping litter, then use regular old arm & hammer baking powder, put down a layer of that, then another layer of litter, you'll find that it works VERY well at controlling odors. The type of food you feed will realy make a diff too.... Oh the ONLY problem I have found is that it does make it a bit dusty when cleaning, but if you run the vacuum hose near the box, that's taken care of as well.