The guru says: Plastic boots usually are double boots, with an insulating, removable liner and a hard plastic shell. That’s one reason why they’re so great. The plastic shell provides fantastic protection from moisture (frozen boots being the bane of any cold-weather mountaineer who has worn leather), while the removable liners make it easy to keep them warm and dry (moisture from sweat and a little snow is inevitable) by sleeping with them in your sleeping bag at night.

Scarpa’s Inverno ($279; scarpa.com) has been around a while but remains a classic plastic boot. And it’s available in women’s 5. You might want to order up as feet swell a little at elevation. They’re very warm by themselves, and although Scarpa makes a “cold weather" liner, I don’t think it’s worth the shockingly high price of $198. Good wool socks and full overboots, such as Outdoor Research’s Brooks Rangers ($135; outdoorresearch.com) will ensure your feet stay warm. Scarpa’s Omega ($350) is a little lighter and designed for more technical climbing than the bulkier Inverno, but also is an excellent cold-weather, expedition-style boot. Sizing may be a problem with the Omega.

That said, it’s also true that advances in boot technology and leatherwork have made leather boots a worthwhile option. They’re generally more comfortable than plastics, too. La Sportiva’s Nepal Evo GTX ($450; sportiva.com) combines Gore-Tex liners with silicon-impregnated leather and an insulating insole for a boot that can take cold, icy conditions. And it comes in a women’s model, built on a women’s last. So I’d give it a look along with the more traditional plastics.

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