We were also having trouble. We spray our yard where the dog stays and put down a bag of stuff, we get from Home Depot, that seems to be working. As for the dog that was covered in fleas before the treatment of the yard. We gave him a bath with Dawn, gave him a Capstar pill(get from vet, starts killing all fleas within 30 mins. $10), then after he is dry gave him Advantage, seems to be doing the trick. Oh yea, we also used a flea bomb for the garage where he sleeps at night.