We pulled up our old carpets and were shocked at the pet stains on the floor. I went to a Janitorial supply store and purchased an enzyme product called "Consume" made by Spartan. We diluted it and used it according to the directions on the label. It worked beautifully! It actually pulled the urine from the wood and left it in clumps to be swept away. The smell has not come back and it has been over a year.