This chapter argues for the necessity of problematizing implicit discourses about authenticity in conducting effective fieldwork. It suggests some specific areas in which this is important including how people (scholars and practitioners) define religion, how “insiders” use specific language in ways that obscure meaning for “outsiders,” and how the default understanding of religion as “belief” too often pervades our assumptions. It illustrates each of these with examples from fieldwork. The observations are drawn from the author’s own field experience, most explicitly from research for Building God’s Kingdom: Inside the World of Christian Reconstruction (OUP, 2015). Christian Reconstruction is an obscure movement that, beginning in the 1960s, laid much of the foundation for contemporary conservative Protestantism. The author’s own background in this group (in the 1980s), combined with outsider analysis rooted in subsequent academic training, provides a setting for reflecting on the contextual limits of language and the ethical issues in “gaining access” to do research in groups, both in terms of its advantages and its disadvantages.