Not sure about how they work on "deer" but they do work on "dear". My wife says she can definitely tell a difference. Everything helps a little but a deer's nose is so good you still better do everything else you can.Just curious if anyone has ever tried Chlorophill tablets to help with scent control? I have a couple of buddies that use them and they tend to think they work so i think i might give them a try. If anyone has any information on them please share.