Most effective flea treatment?

[BettyCatKitten]

I'd be very grateful if you fellow cat owners could advise me on what you consider to be the current, most effective flea treatments.
Also how/where you purchase them.
Many thanks

I use Advantage or Effipro. Find the cheapest online, a few months of one then the other. Find it works well. Plus the cheapy spray from Wilkos for around the house.

Broadline, advocate/prinovox (both same stuff)/ activyl are my favourites.

Thanks for your replies