David is one of a group that refined what we know as Parkour. There is Yann Hnatura, Williams Belle, Chau Belle-Dinh, Sebastien Foucan, Guylain, Laurent Piemontesi, Malik Diouf, David Belle, and Charles Perrier. Recently many of the original traceurs have since gotten back together under the banner of
TheMouvement. Others (e.g. Tim Shieff, Erica Madrid and others) were drafted in as an advisory board as well.
If you're looking to train with the original traceurs, look them up on Facebook on their athlete pages, and drop them a line. They run workshops, classes as well as just training themselves. Many of the original traceurs still live & train in Lisses, though others are scattered (Sebastien is in London, Laurent in Italy, Yann in Africa as far as I remember, etc)