Probably one of the best books that really influenced me is Gavin de Becker's Gift of Fear. Gavin has some really good insight into fear management, gut instinct and essentially developing those primitive skills that can help you when you get into trouble. If you are a real student of the martial arts / self defense, security or law enforcement, I would really recommend that you check out this classic. I mentioned it during the new Self Defense Concepts class and it's already a hit with some of my students. Check it out! Jd