Should I wear my touring helmet on the uphill, or just put it on for the descent?

This is a debated topic in the backcountry community. Arguments for wearing it uphill include protection from overhead hazards (cornices, seracs, rockfall) and not having to stop at the top to dig it out. Arguments against include reduced hearing, added weight, and discomfort. The safest practice is to wear it whenever you're in terrain with overhead hazard, but many experienced skiers remove it on mellow, low-angle approaches. If you remove it, secure it to your pack — don't strap it to the outside where it can snag on branches or fall off.