this is great stuff. much better than frontline. only reason i gave 4 stars is because it says on the box that you CAN wash your pets after putting on the advantage. i dont care what the box, vets, or anyone says, this WILL mess up the treatment and your $ goes down the drain....no pun intended. i've been working with animals for a long time....wash and groom your pet, administer the advantage, and wait 4 weeks until you groom and bathe again. its makes giving the medicine, and your grooming schedule easier to remember. plus you really dont want to bathe your dog anymore than that. anyway, GREAT product other wise!