The One Young World event – running from 18-22 October at the David L. Lawrence Convention Center in Pittsburgh – has been produced by Brand Fuel for the third time.
It is the first time the event has been held in the US, and it will move to Johannesberg in 2013.
A total of 1,500 young leaders from 180 countries around the world joined for the annual summit event.
The 18 to 30-year-olds debate issues including health, the environment and business, guided by counsellors, who are experts in their fields.
The One Young World concept was founded in 2009 and at the summit events in 2010 and 2011 delegates were guided by a line-up of counsellors that included Archbishop Emeritus Desmond Tutu, Bob Geldof, Kofi Annan, and Jamie Oliver.