My young daughter spilled a big cup of milk on the carpet and didn't tell me. Within a month there was a smell that overpowered the whole living room. I tried EVERYTHING, believe me. I finally came across this product and for the 1st time in almost 2 years the smell almost disappeared! I got 2 more cause the smell came back and the area is about 1sq metre. Same result. I'm going to get 1 more and I think that's the ordeal over!