Comprehensive sexuality education (CSE) aims to improve knowledge and understanding, and to correct misconceptions about sexuality. It provides young people with age-appropriate, scientifically accurate, culturally relevant information about their bodies, health, relationships, and rights. Evidence shows that high-quality CSE can delay sexual initiation and reduce sexual risk-taking, while increasing contraceptive use. While access to CSE remains uneven, many young people lack essential knowledge and skills. CSE is a curriculum-based approach that teaches children and young people about the cognitive, emotional, physical and social aspects of sexuality in a culturally-appropriate way. It can be delivered in both formal and non-formal settings. The international technical guidance on sexuality education provides a rights-based framework that can be adapted to local contexts. There is no evidence that CSE increases sexual activity or risk‑taking, nor does it encourage earlier sexual behaviour.