Augusto Boal developed his Theater of the Oppressed in Sao Paulo, Brasil, and is currently working in Paris at the CEDITADE (Centre d`Etude et de Diffusion des Techniques Actives d`Expression). He also travels and lectures extensively in other countries.
Check out his book Games for Actors and Non-actors for tons of good games and techniques.
Improv means never having to say you`re sorry --- Ali McGraw