Unlike light touring, in which binding selection is an afterthought to the more important boot decision, for backcountry/telemark skiers. Bindings are a big decision. In bindings you're presented with three basic choices:

Three-pin bindings (also known as 75 mm), have a trio of metal pins that fit matching holes on the sole of the boot. The binding fastens by manually clamping a metal plate, called a "bail," onto this toe lip. Remove skis by releasing a catch on the bail, allowing it to swing free. Three-pin bindings are a bit more of a nuisance to fasten than automatic bindings. But they are strong, and their width gives better control of the ski in difficult terrain or for Nordic downhilling.

Cable bindings clamp down on the boot toe with a "bail," while a cable wraps around your heel to provide additional stability. A notch in the boot heel holds the cable in place. These bindings have two major advantages: They don't allow the heel to lift as high as other bindings do, increasing your cornering and edging control; and they can pop completely free in a wicked fall. Cable bindings are favored by hard-core telemarkers but cursed by beginners due to their complex attachment.

Your third alternative is a system-type binding (in which boots and bindings were developed as a "system" to compete with three-pin bindings). Two backcountry styles exist: Profil BC and NNN BC, which are the backcountry equivalents of the similarly named light-touring bindings. The Profil BC has yet to prove itself strong enough for heavy-duty skiing, although future designs look promising. Currently, the NNN BC is stronger, but still it doesn't rival the three-pin binding for heavy-duty use. It is available in both manual and step-in styles.

Move on to Telemark & Backcountry Equipment - Boots

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