The General Assembly on 17 December 1999 in its resolution 54/120, endorsed the recommendation made by the World Conference of Ministers Responsible for Youth (Lisbon, 8-12 August 1998) that 12 August be declared International Youth Day. The Assembly recommended that public information activities be organized to support the Day as a way to promote better awareness of the World Programme of Action for Youth to the Year 2000 and Beyond, adopted by the General Assembly in 1995 (resolution 50/81).
http://www.un.org/depts/dhl/youth/index.html
http://www.un.org/esa/socdev/unyin/iyouthday.htm