This book contains accounts of state-of-the art approaches to the physics of granular matter, from a widely interdisciplinary and international set of experts in the field. The authors include theorists such as S F Edwards, J Krug and J Kurchan; the book is also unique in reporting current experimental approaches with, importantly, a detailed account of new techniques. It will serve as an invaluable handbook for all researchers, both novice and experienced, who wish to get quickly directed to open questions in key aspects of this challenging and topical domain.