The International Symposium, "Implementing Sexuality Education", took place in New York on 27 April 2011. The Symposium was hosted by UNESCO and convened by the UNAIDS Inter-Agency Task Team (IATT) on Education. It preceded the UNAIDS IATT on Education's members meeting on 28-29 April 2011. The one-day symposium brought together over 50 participants representing more than 30 multilateral, bilateral and civil society organizations, and government representatives concerned with HIV and sexuality education to: Discuss the results and implications of a groundbreaking international study on the cost and costeffectiveness of comprehensive sexuality education programmes in six countries; Review the country situation and operational plans with regard to addressing HIV knowledge among young people through comprehensive sexuality education, with a focus on the 17 countries prioritized in the UNAIDS business case on young people; and Identify areas of collaboration and ways forward in addressing HIV knowledge through comprehensive sexuality education. This report synthesizes the key issues discussed at the Symposium and observations, conclusions and recommendations emerged from the meeting.