I've been going nuts with this for months now. I have an accumulation of cats, all neutered or spayed. A couple of them apparently felt insecure about their standing in the feline heirarchy and started marking stuff. I've tried a variety of deodorizing products and procedures (Feliway, vinegar, etc.) and nothing's worked. I'm tired of making a religion of sniffing everything, closing doors that haven't been closed in years, and spending all my off time scrubbing the bottom twelve inches of every room in my house. Any suggestions? Transferring all the cats to permanent outside duty isn't an option, especially the way this winter's been going.