The coastal fleas here are resistant to Frontline. I've talked to other owners, and they say the same- every flea treatment out here, the fleas adapt to. Reeeally frustrating. Right now bathing, manually picking them off, and praying the frontline does SOMETHING is what I'm doing. I'm still getting bit at night, though. Going to invest in a flea comb and look into treating the yards....sigh. Also need to set up our flea trap, which works. The dog has fleas, but thankfully there aren't many in the house- yet.