No-Mark works. I was skeptical. My cat had been spraying in the house 3 times a day for oh, about a year. We’ve had it. He always has an issue whether its with a neighbor cat taunting him from outside, or we don’t move fast enough to give him his treats. But we spray this all over the house and he’s fine. It worked from the first spray. We now buy a bottle every 2 weeks because its cheaper than replacing furniture. Also, it smells good, not chemical or anything and doesn’t leave a stain if i spray it on my couch. I think you have to try it to believe it! I’m going to buy stock in this.