There are a zillion choices out there. Winter sports stores and hunting outfitters have the best selections. I have liked the two part liner glove and over-mitt approach - mine is from Cabela's, and the over-mitt has little magnets sewn into the polartec fleece so that you can fold back the finger cover and the thumb cover and they stay put. New thing this year seems to be the nylon and polartec hand muff on a belt, and the hand muff has a zipper pocket where you can stash a chemical hand warmer. This would seem to be a great thing for waiting around, or for operating a wired shutter release on a camera set up to shoot a nest. However - it hasn't been cold enough for me to bother to deploy it! It's a lovely neon orange, so I don't get mistaken for a turkey, duck, or deer.