Have you actually seen fleas in your carpet or on your furniture???? If not ... then probably just treating the cats will be enough!!!! Some cheap flea products just make the fleas jump off of the cat onto the floor etc.... but Revolution kills them so they will not move to another location!!! I wouldn't freak out just yet and go through alot of expense and hassle by treating your whole house until the cats have been treated and you actually see that you have an infestation elsewhere!!!

GOOD LUCK!