My cat won't stop peeing in the furniture. We've tried several things, guaranteed to stop it, but they haven't. Any ideas?

Your cat is trying to tell you that he either has a health problem or there's something wrong outwardly causing him stress.

First things first, a vet visit. It could be as simple as him not liking the litter on his paws, so switch up litter. Or it could be a health issue, like kidney disease or something else. Either way, take him to the vet.

If he has a clean bill of health and the litter isn't an issue, I would take to looking OUTSIDE. Yes, OUTSIDE. There could be a number of critters or another cat that started roaming around and he feels he has to scent up your home so as NOT to have these "intruders" make a move.

I know it sounds crazy but so many people assume that cats just start up and peeing on things for no good reasons, but hey: they can't talk and tell us what's wrong so we have to pick up the clues. Vet, litter, outside.

It HAS to be one of these.

Keep the litter box very clean, and add a second litter box. The advice to take him to the vet for testing is correct. The vet might also suggest that the cat be neutered.

Have you had the cat checked by a vet? Do you have other pets in the house? Is the cat actually peeing or is it marking the furniture as territory? In any case, talk to a vet to find a solution.