Lenny,
I did apply the Frontline to the pup and he still has fleas. I am thinking of doing another application, but I have to wait a while, as they say not to do it for at least two weeks. I also used Frontline on the three cats, and they have also had fleas.
Frontline has always worked for me before, but I"ve read many threads on various pet forums where people say it is not working.
Patty