This paper elucidates evidence which underscores anxieties and panic about sexuality and sexual behaviour of young people influenced by movements advancing a distinct religious identity, and the implications for advocacy on advancing Sexual and Reproductive Health and Rights (SRHR). Synthesised in this document is evidence from two countries - Bangladesh and India - on Comprehensive Sexuality Education (CSE), an area of controversy (to varying degree) in both countries. Evidence from each country stem from national studies on the influence of religion on CSE, and are qualitative in nature. The collated evidence is supported by secondary literature, employed to frame the complex ways in which state policies and people’s perceptions link controversies around CSE to religious beliefs and interpretations, socio-political movements bearing fundamentalist ideals, and state ideology and response. This paper is structured as follows: the section that follows the introduction contextualises CSE within the broader economic and socio-political environment; the second and third sections hone in on evidence from Bangladesh and India about the role of religion in shaping discourse and perceptions on CSE; and the fourth section presents a conclusion, followed by a section on recommendations for future action.