We live in South Texas...breeding grounds of the BIG FLEA! Because of the heat and sandy enviroment, we have FLEA SEASONS here. We treat our yard with Dursaban (anything from yard and garden centers that has dursaban in it). We do not dulute it alot either, we make it strong. But first...I STRESS THIS ALOT: Be prepared to keep all your animals INSIDE or somewhere else for at least a full day. Spraying your yard in the late evening is best. If its possible, stay in a motel for one night or at a friends house, get some of those d-con or raid room bombs...set them off at the same time you spray outside. After twenty four hours or longer...I gaurantee you won't have any fleas. Do it again two weeks later. We did this on a rent house because it was covered with fleas....its been three years and haven't seen a flea since. We also only treated the yard once a year after that. We bathed our pooches and kitty before going home, we also use the spray mist they sell over the counter too...but only if we leave, like walks down the neighborhood or park. So no 'hitchhikkers allowed' on our poochies! Just a few ideas...we are scratch free! I know it takes time and some work, but its nice seeing your animals sleep peacefully!