Appreciative Inquiry: an emerging direction for organizational development by David L Cooperrider, Peter F Sorensen Jr, Therese F Yaeger, Diana Whitney (eds) 2001
Jemstone Consultancy Review
This was my first introduction to the writings of David Cooperrider and I still refer to it regularly. The collected papers cover the development of the theoretical base for AI and early application in the field. If you want to understand WHY it works as well as how to do it, this is a great book that will last you a long time.