I want to love this caddy, because it's very attractive and functional, and did for the first while. But it is absolutely not waterproof or mildew resistant. Right away it began mildewing (and it's not an issue anywhere else in my bathroom), so I actually sanded it off and sealed it with a varathane. It lasted about 2 years with that, but where the water pools at the seams it has begun to mildew further, and all in the round holes where frequent use has worn the varathane off. I love this, wish it was truly ok to be in the shower. You MAY have luck if water isn't actually hitting it, so perhaps suctioned to the rear wall of the shower.