It's important to know how you'd handle yourself in a dangerous situation.
Mircea Dimian recommends learning Krav Maga, a self-defense system developed for the Israeli army. Dimian calls it "the only worthy defensive art of fighting for those who don't embrace violence."
One woman who studied Krav Maga created her own self-defense system for women, the Soteria Method, and some of her techniques involve fighting off an attacker with your high-heel shoes.
If you know basic CPR, says Tanya Keeter, "you can save the life of your family members, friends and strangers."
If you've forgotten what you learned in high-school health class, the American Heart Association website lets you search for online and classroom training sessions in your neighborhood.