How do you get rid of flea on cats?

I have actually tried the diatamatious earth in the yard once. I'm not sure how effective it really is. And with fleas, all you need is two of them in the house, and the outside doesn't matter anymore. So I gave up on that, and focused on the house. I think killing everything in the yard here would be next to impossible anyways, and I have a "control team" that lives outside, otherwise known as a whole lotta anoles! The hardest part with the orthoboric acid is not vacuuming for 3 - 4 weeks. And it doesn't have the same effectiveness if you live in a house that is mostly wooden floors, tile, etc... You can sprinkle it under furniture cushions and the like.