We have 3 young kids and have been searching for a mattress cover that is truly waterproof. This is the 4th or 5th brand we've tried, and we finally have found one that does what it says. Given that we have been misled in the past by others saying they are waterproof, only to find a wet spot on the mattress after an accident from one of the kids in the morning, we tested this one out before putting it on the bed - no water leaked through even after letting it sit for several hours. Also, the material is soft and quiet (i.e., no plastic feel or sound). We are very happy with this product.