Inge Nielsen has collected an impressive number of plans, drawings and photographs which illustrate the architectural settings of ‘mystery groups’, ‘religious associations’, Diaspora Jews and early Christians. This helpful compendium of archaeological material now updates and complements earlier works, such as L. M. White, The Social Origins of Christian Architecture, 2 vols (1996–97). N.'s ‘general conclusions’ are largely typological, however, not social-historical. Readers here will learn that religious groups met in spaces which conformed to either a ‘temple-type’, a ‘cave/grotto-type’ or a ‘banqueting/house-type’ (241–53). Scholars of ancient religion will likely be underwhelmed.

N.'s study is organized into three parts: ‘The Architecture’ (Part I), ‘The Cultic Functions of Religious Groups’ (Part II) and ‘Considerations of Typology’ (Part III). Part I proceeds chronologically. It reviews the pre-Hellenistic, Hellenistic and Roman evidence.

Ch. 1 offers a short discussion of ‘external parallels’ for mystery groups (9–12). Buildings from Phoenician Crete and Cyprus indicate the cultural importance of dining within sanctuaries and temples, a point amply documented by evidence for benches and dining-halls. Ch. 2 collects evidence for ‘banqueting installations’ (13) in seventh- and sixth-century b.c. Greece. It then summarizes archaeological work at Eleusis, Samothrace, Lemnos and Thebes. A discussion of related material, pertaining to the followers of Pythagoras, Orpheus and Dionysos, follows (25–30).

Ch. 3 examines sanctuary evidence from the Hellenistic to Roman periods. Here, N. showcases her strengths, deftly surveying a wide variety of architectural evidence: at Pergamon, Ostia, Isthmia, Alexandria, Soli, Delos, Gortyn, Priene, Praeneste, Pompeii, Cenchreae, Ephesos, Palmyra, Petra, Dura-Europos, Athens and Rome (34–106). The presentation is descriptive, but an appreciable amount of work has gone into collating the reports from which these data have been gleaned. Ch. 4, titled ‘Rooms for Religious Assemblies outside the Sanctuaries’, catalogues the Mithraic evidence, as well as ‘Rooms for the Jewish Groups in the Diaspora’ (170–84), and the sparse archaeological record for Christian worship spaces prior to Constantine (183–94).

These four chapters represent the major contribution of N.'s study. In future volumes, I would suggest, however, that the series' editors insist on more specificity from their authors when it comes to citations from archaeological reports. Some of N.'s references — her discussion of Ostia's sanctuary of Magna Mater (90–3), for example — are too generic to help researchers fact-check details or follow up on an excavator's interpretation; precise page numbers are needed. The editors also need to address the handling of images. Pl. 1, a photo of Eleusis, is credited to Pinterest, a third-party image-hosting site; pl. 13 is a third-party reproduction of a photo whose rights are held by the American Academy in Rome. For a series that aspires, in the words of its boilerplate, ‘to the best academic international standards', these are not the best practices.

Parts II and III of N.'s book are also not successful. N. demonstrates no engagement with sociological or anthropological approaches to group initiation as found in V. Turner's work on community-formation (The Ritual Process: Structure and Anti-Structure (1969)) or as explored in contemporary settings by H. Bowden (Mystery Cults in the Ancient World (2010)). A two-line excerpt on p. 1 — from Arnold van Gennep, Les Rites de passage, a work that appeared more than a century ago (1909) — is the closest N. comes to giving her book a theoretical orientation. N. also shows no awareness of the pitfalls of making comparative religious claims. In a book that connects many people, times and places, J. Z. Smith's work on mystery cults (Drudgery Divine: On the Comparison of Early Christianities and the Religions of Late Antiquity (1990)) should have been foundational. One of Smith's arguments is that the search for ‘parallels’ in religious history — ritual, philosophical, even architectural — must account for distinctions between ‘analogy’ and ‘genealogy’; just because features of one religion might look like those of another does not mean they came from the same source. N. overlooks this point and speculates freely about religious borrowings (225, 229).

These are missed opportunities. If the author had been pushed to read more widely in religion and social history, this book could have engaged scholars who might not naturally pick up a volume weighted with archaeological plans.

And yet it is the archaeological omissions here which are truly baffling. Many of the author's summaries about Jewish and Christian architecture are not up-to-date or, worse, her claims have already been disproven. J. Magness, The Archaeology of Qumran and the Dead Sea Scrolls (2003), as well as Magness' work at Sardis (AJA 109 (2005), 443–75), renders N.'s discussion of these sites (172, 179–80) obsolete. Important works on Christian architecture — among them, A. M. Yasin, Saints and Church Spaces in the Late Antique Mediterranean: Architecture, Cult, and Community (2009) and K. Bowes, Private Worship, Public Values, and Religious Change in Late Antiquity (2008) — are also missing. Either might have led N. to revise her concluding paragraph. Did Christian architecture really develop from ‘a private context to a “canonical” form’ (253)? Or is there slightly more to this story?