Family and religion have been shown to be important to the majority of people in both the United Kingdom and the United States. Numerous research studies suggest that childhood relationships and environment are influential to mental health and well-being, with research on religious families significantly increasing in the last few decades. The purpose of this study is to explore counselors’ experiences of the influence of a fundamentalist religious upbringing on mental health and well-being in adulthood, across the Abrahamic traditions within the United Kingdom. The primary objectives are to psycho-educate professionals to recognize and understand the influence of a fundamentalist religious upbringing on mental health and well-being in adulthood, and to add to the sparse literature on this largely hidden topic. In-depth, qualitative, non-structured interviews were conducted with eight counselors (one withdrew at pre-analysis stage), who were collaborative co-researchers throughout the process. The focus of this article aligns with one of the interpretative readings of the interview transcripts undertaken by the researcher and co-researchers during the research process, namely appraising issues of power and control. The author outlines her insider researcher background, chosen methodology, co-researcher recruitment, and ethical considerations, before sharing the co-researchers’ stories around the power and control dynamics of a fundamentalist religious upbringing. The co-researchers’ adult religiosity is briefly outlined, before some brief reflections conclude the article.