Diana G. Tumminia holds emeritus status at California State University, USA, where she taught a variety of courses: social psychology, sociological theory, race relations, and women's studies (Women in Spirituality). Tumminia is considered an expert in the field of social movements, in particular, new religious movements. She has authored numerous articles on teaching, religious practices, and ethnographic studies. James R. Lewis is currently an associate professor in the department of history and religious studies at the University of Tromsø, Norway, and a leading scholar of new religious movements. His reference volumes, Cults in America and The Oxford Handbook of New Religious Movements , both won CHOICE book awards.