This impressive work constitutes an important and timely addition to existing dictionaries of psychoanalytic ideas. It is not intended to replace the reading of Bion’s original texts nor is it a biography of W.R. Bion, the man. A brief history of Bion’s life is offered in the introduction to illuminate the conscious and unconscious factors that may have been an influence on his work, but the aim of this volume is to serve as an insightful and comprehensive guide to the often obscure meanings and terms explored and created by Bion throughout his many years, first as a psychiatrist and later as a psychoanalyst. It is an essential companion to the works of Bion that brings clarity and understanding to his absorbing concepts and is a vital addition to the library of anyone who has read and wondered over the writings of W.R. Bion.