Since the 1960s, the proliferation of cults, sects, private religions, invisible religions, and esoteric belief-systems in general has left sociologists of religion struggling to define their core subject-matter. It has seemed increasingly unsatisfactory simply to assume that religion happens in churches (or, indeed, that Churches are necessarily concerned primarily with the promotion of religion). As a result there have been numerous attempts to impose order on the field. In one such effort, A. L. Greil and T. Robbins ( eds.) (Between Scared and Secular, 1994) distinguish between religions (as conventionally understood), on the one hand, and ‘para-religions’ and ‘quasi-religions’ on the other. Para-religious phenomena ‘involve expressions of ultimate concern’ but make no claim to be religions because no supernatural beliefs are involved. Examples include psychotherapy as practised in a communal setting and ritualistic aspects in corporate and consumer life. Quasi-religions do make supernatural claims but these are ‘anomalous given the American folk category of “religion”’. Occultism, New Age spiritualism, astrology, and Scientology are cited as exemplars. The fact that the last of these has been involved in a long history of political and legal wrangling in order to have itself recognized as a Church illustrates the difficulties of defining clear boundaries in this particular sphere of sociological interest.