A few suggested items... illustrated in unlifelike color!
Here are a few of the clothing items I think are essential for winter camping. While I am a big fan of "miracle fibers" (read that: Gore-Tex and fleece), there is a lot to be said for the old standards, like wool and even, to some extent, leather and cotton.

Let's talk about the cotton for a second, since I can hear some of you laughing already. Any experienced backpacker/climber/outdoorsperson knows that cotton is a useless fabric in most situations. As the old maxim says, "cotton kills"... and that's certainly true in temperatures near and above freezing . However, in deep cold conditions -- the real FUN stuff -- cotton makes a useful, breathable outer layer. Then again, I wouldn't take it mountaineering: if you get it sweaty (wet) it's a problem, and its insulating properties are zero. So while its value is limited -- most importantly, don't use it for insulation (chamois shirts and cotton socks are out) -- it may have a place on your pulk or toboggan.
Okay, enough chaff. Bring on the hardware:

HEAD

Headgear is key: not only does it preserve a lot of body heat, but it gives you something easy to take off if you overheat. Be careful, though: sweaty heads ice over quickly. I usually wear a close-fitting hat (see below). In serious cold I switch to an open-face balaclava with my neck gaiter pulled up underneath to cover my mouth and nose. This is also how I tend to sleep in deep cold.
HAT

Wear a hat. Fleece or wool are both good choices. I prefer watch caps or similar close-fitting designs, since they make putting your hood up an easy task. I sometimes carry two hats, one a little larger than the other, for layering. You can stuff damp glove liners into the top of a more spacious hat, and your body heat will dry them out.
BALACLAVA

A balaclava looks like an executioner's hood and provides full coverage for your head. These leave either your entire face exposed (good for ventilation) or have just an eye slit (warmer). Either way, make sure you buy one that's long enough so the bottom edge will meet your neck gaiter/jacket collar (or whatever you're wearing) to ward off drafts. Again, I often carry two: a thin polypro model, and a thicker fleece one for when it's chilly. Some versions combine a balaclava with a face masks (see next).
FACE MASK: Usually neoprene (wetsuit material) or fleece, this provides crucial protection for your face, which - as it spends all day breaking trail through the wind - is vulnerable to frostbite. They seem ridiculous until you need one.
BODY

Think layers. Long underwear, then an insulating layer, then an outer layer to block wind. Several thin layers will keep you far warmer than one thick layer and provide more versatility so you aren't too hot or too cold.

When I'm moving I usually wear long underwear, minimal insulation, and my wind layer. The less you have on, the better you'll ventilate and the less likely you are to be sweaty-damp when you stop. If there's no wind (Is there ever no wind?), I'd add some insulation and drop the wind layer, again for improved ventilation.
WIND LAYER

A good start to your wind layer is an
ANORAK.

Anoraks can sometimes present a ventilation problem, so breathable material is best. Nylon works well here, and cotton is a possibility... just don't get caught in the rain, and don't sweat it up. Waterproof/breathable anoraks are also good. Many have a "kangaroo" pocket in front, which is a very handy thing.
WIND PANTS
You should also have some pants of material similar to your anorak to block the wind down below. Spend a little extra to get full-length leg zippers; ankle zips or knee-high zippers won't fit over winter boots.
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HANDS

Your fingers have a lot of surface area, and are very easy to frost. Gloves are great, but mittens keep your hands warmer. As in everything, layering is key. I start with a thin pair of glove liners, cover them with wool or pile mittens, and top them off with a good pair of wind-blocking
 OVERMITTS.

Think of overmitts as wind layers for your paws. Features of good overmitts include: forearm-high gauntlet construction, reinforced/textured palms and thumb for gripping, drawcords at the wrist and at the top, and idiot cords to hold the gloves onto your wrists if you take them off when it's windy.

MITTENS: wool or fleece, these go -- you guessed it -- inside the overmitts. Make sure they're not too tight or they'll constrict your circulation. Especially since you'll also be wearing...
GLOVE LINERS: A thin pair of glove liners/liner gloves is essential; carry several pairs. When you're traveling and the temps aren't too bad, you'll probably just wear liners, or liners with overmitts. Having spare liners on hand (Ha! Get it?) means never having bare, sweaty hands, and the first time you grab a cold metal tent stake with damp hands you'll appreciate the idea of having a layer of polypro between your skin and the metal.

FINGERLESS GLOVES: Not essential, but nice to have. A good halfway point between plain liners and full-on mittens. I've used the same cut-down pair of wool military-surplus gloves for years.
FEET

Feet and fingers are two valuable, but vulnerable assets. You can still get yourself to safety with frozen hands, but if your feet freeze you're pretty well done for. So, item number one for me is a pair of...
 MUKLUKS.

Mine are made from moosehide and canvas; if they ever get soaking wet I'll be a sorry pup, but in below-freezing temps they're amazing. The other major downside of mukluks, besides non-waterproofness (which is actually a good thing when it's very cold), is the fact that they have soft soles, sort of like moccasins. This is fine in the snow, but on a rough/rocky trail it can be punishing. That's when you might consider a pair of...
PAC BOOTS. I have a love/hate relationship with these things, which I think is only healthy. They're big, beefy, and warm -- so on rough terrain your feet take less of a beating than they do in mukluks. Since pacs are half rubber, they're also better-suited for slush, creeks, or variable temperatures. But, again, they're half rubber -- so your feet are going to get damp (condensation) even if the outsides of the boots stay bone-dry. The key (I think) is to have some means of drying your insoles and socks every night (i.e., big honkin' campfire), or spares that you can wear while you freeze-dry (a wholly unreliable process) the other set.
SNOW SPORT BOOTS: You know the ones. Usually leather on top, rubber below, as comfortable as lightweight hikers without a lot of bulk, but well-insulated. They fit great into snowshoe bindings or on the footpegs of a sled. Great around town or for backyard recreation, but I wouldn't take them into the woods -- and definitely on on an overnight trip -- for the simple reason that there is no separate inner bootie to remove and dry when you make camp. If they get wet, they stay wet (until they freeze) and so do your feet.
SOCKS:  As my friends can tell you, I love wool socks. I wear them in the winter, I wear them in the summer. I wear them to work and on my days off. I love them. They're great insulators, they keep your feet dry, and it takes them days before they really start to reek. That said, I must confess that I've fallen victim to the charms of fleece socks. They're just as toasty, lighter, and more comfortable. I usually combine the two when it's very cold: fleece over wool (which, in turn, goes over a polypro liner).
(c) 1997-2008 A. Dundas. Original content and artwork (I use that term loosely) are copyrighted and may not be used without permission.
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