This book is a must for anyone with a serious interest in the ASC. Michael Young has given a fine description of the growth and development of the ASC before and during WW1. This is no mean feat since the Corps was everywhere at once, and this makes it mauch harder to describe than, say, a divisional history.
It has over 100 photos, the bulk of which are unpublished. Many researchers will find the 20 appendices (which comprise half the book) to be particularly useful for identifying where and in what capacity a particular ASC unit served. For these two things alone it is excellent value for money.