While bear attacks on humans are rare, they do happen. Most seasoned outdoorsmen who do have bear encounters come out unscathed because they know exactly what to do when they're confronted by several hundred pounds of teeth and muscle. The following video was shot for ABC's Survival Week.
How To Survive a Bear Attack
Never Run Away - stand your ground or the bear will think that your are prey. You will not outrun a bear.
Talk in monotone - talk to the bear like he's a person that you're trying to calm down.
Slowly back away. Don't make any fast movements.
If it's a black bear, be aggressive and try to intimidate it.
If a grizzly attacks you, cover your face and neck and try to get on your stomach. Roll back to your stomach if he flips you.
Always let them know of your presence by talking, using a whistle from time to time, or putting something on your pack that clanks when you walk.
Get bear spray and a bear whistle.
It's good to have a plan B if intimidation and noise don't get the job done. Bear Sprays and pepper sprays will disorient a bear and sting their eyes and noses bad enough that they won't want anything to do with you.