Also here is a pretty good site detailing concepts

http://www.fastdefenseofnewyork.com/fastdefense.htm

They are all over the place but the concepts are all the same. its about awareness of surroundings first and foremost. How to evade and escape a potentially dangerous situation. It then focusses on combat and how you stand up when confronted by a nasty spitting tosser who wants to rip your head off. Its controlled yes but as real as it gets to having someone in the street stand in your face wanting to hurt you.

Like i say. Worth a look. Many a martial artist has had a shock doinbg this course.