Sexual and reproductive health rights are agreed in international laws. In recent years, however, diminishing reproductive health rights have been seen across the globe, including limitations in the provision of comprehensive sexuality education (CSE) for adolescents and young adults (AYAs). CSE is defined by the World Health Organization as “a curriculum-based process of teaching and learning about the cognitive, emotional, physical, and social aspects of sexuality.” CSE aims to empower AYAs to realize their health and dignity, consider the impact of their health choices, and develop respectful relationships in order for them to lead their best lives. Recognizing these increasing threats to what AYAs need and want, five healthcare professional associations engaged in discussion with UN agencies and each other about advocating effectively for evidence-based CSE; this commentary summarizes five policy statements motivated by these discussions and registers publicly our collective organizations’ support for CSE in schools. We present four strong common themes that underpin these statements: collectively, they offer a compelling case for the ongoing promotion and scale-up of CSE within national curricula in schools. They also highlight the roles of healthcare professionals in advocacy and in practical capacity-building support for schools, families, and communities.