[corgimom]

That is interesting, because my vet said the frontline plus is effective for fleas for 3 months, but ticks for only 1 month - so I would assume if you live in an area where you have a heavy infestation of ticks(especially where it is warmer year round) then you would apply it every month. I just put on the frontline plus for November and don't plan on using it again until February. Here is the link which goes over frequency of application. I guess one has to decide whether monthly or every 3 months is needed for their pets.