We had an awful time with them recently, and our cats are indoor only. We had the exterminator come through, and then when that didn't get rid of them completely, we ordered Flea Stoppers powder online. It worked very well. We tried some of the off-the-shelf carpet powder, and it was a temporary fix at best. Just Google "Flea Stoppers," and you should be able to find it. We also treated the cats regularly.