The Art of Facilitation is written in simple language. It cuts through the academic tendency to complicate this domain, and in doing so displays the authors mastery of it.
The Art of Facilitation elucidates what it takes to facilitate groups powerfully and provides pathways, tools and processes for this.
This book will provide people new to facilitation with an intellectual analysis of it and old hands clear pathways to doing complex things simply. I use it all the time as a resource in my pratice as a professional facilitator and it is the required text in facilitator training courses which I lead for Zenergy.
I would also recommend Hunter et al's other books: Co-operacy, The Zen of Groups, The Essence of Facilitation.