In 2009, UNESCO published the International Technical Guidance on Sexuality Education (ITGSE): An evidence-informed approach for schools, teachers and health educators. The purpose of the ITGSE is to assist education, health and other relevant authorities in the development and implementation of school-based sexuality education programmes and materials (UNESCO, 2009). The publication was released in two volumes: Volume I, which focuses on the rationale for sexuality education and provides sound technical advice on the characteristics of effective programmes; and Volume II, which focuses on the topics and learning objectives to be covered in a ‘basic minimum package’ on sexuality education for children and young people from 5 to 18+ years of age, and includes a bibliography of useful resources. In 2016, UNESCO began a process to update the ITGSE, consisting of a literature review of the evidence and lessons learned since the release of the original publication; a stakeholder consultation on sexuality education held in October of 2016; an online user survey; and an expert, Comprehensive Sexuality Education (CSE) Advisory Group established to inform the process and its findings. This report summarizes evidence-informed conclusions, expert recommendations and current practice for curriculumbased sexuality education for ages 5-18+ and provides preliminary, overarching changes to Volume II of the ITGSE for consideration by the UNESCO CSE Advisory Group.