We were not aware our cat had marked our carpet in a few areas until it was dried in.  This product got the pee out so good when it came time to move we got 100% of our security deposit back--and they check really good for that kind of stuff.  The carpet looked as good as new.  Whew!  We used a carpet shampooer after this product and it worked just like it said it would.  Thank goodness.