108 Book Reviews Lloyd Ridgeon (ed.) The Cambridge Companion to Sufism. Cambridge Companions to Religion. Cam- bridge: Cambridge University Press, 2015. xvi + 310 pages, figures, index of names of individuals, index of technical terms and names of groups, index of English terms and place names. Paper. ISBN 978-1-107-67950-4. US $29.99. I have always found the Cambridge/Oxford/Routledge/Wiley-Blackwell Com- panion to be an odd genre. With the exception of the Bloomsbury Companions, which are aimed directly at researchers, these Companions are not for experts, nor are they for Dummies. They are not handbooks, textbooks, or Festschriften. They are, according to their publishers’ basic pitch, accessible, written by experts, intended for non-specialists. Unfortunately they rarely define the crit- ical terms of that equation: accessible to non-specialist readers. Does acces- sible describe a particular linguistic register, a low expectation of prerequisite knowledge, or a manageable level of detail? And who are these non-specialist readers? Undergraduates in an introductory course? Graduate students in the process of becoming specialists? Experts looking for a quick entrée into another field? The home shopper browsing online bookstores? A survey of exemplars from the genre reveals that many contributors do not always have a clear sense of the answer either. Some authors write genuinely introduc- tory essays, while others assume considerable prior knowledge. Some authors write straightforward summaries of one aspect of the field, while others write jargon-packed essays about a particular problem or debate that our poor non- specialist must take great pains to penetrate. In my view, for a Companion to succeed qua Companion, the entire volume should hang together holistically, each chapter complementing the others, guiding the non-specialist into and through a particular field of study at a predetermined level of detail and com- prehensibility. Clearly, responsibility lies with the editor to assemble a stable of qualified authors, corral them into writing complementary chapters for an explicit purpose and readership, and all executed in an “accessible” style. This is a Herculean task and the reason that many Companions fall short. Nevertheless, these are the only standardizable criteria by which one can assess such an unusual genre. Therefore, rather than treating a Companion as a loose collection of conceptually linked but disparately targeted essays, the reviewer better serves prospective readers by assessing 1) how well the editor envisions and defines her readership; 2) how well the editor conceptualizes and subdivides the topic, carefully balancing breadth with depth; and 3) how well each author implements that vision in service of the topic. For readers looking for an introduction to Sufism that assumes no prior knowledge there are more than a dozen such titles currently available in © koninklijke brill nv, leiden, ��16 | doi 10.1163/ ��105956-1�341�86