The 2003 Special Olympics World Summer Games were hosted in Ireland, with participants staying in various host towns around the island. Events were held from 21-29 June 2003 at many venues including the Royal Dublin Society in Ballsbridge and the National Basketball Arena in Tallaght, Dublin. Croke Park Gaelic games stadium, in Dublin served as the central stadium for the opening ceremony, even though no competitions took place there. Belfast was the venue for roller skating events (at the Odyssey Arena ), as well as the Special Olympics Scientific Symposium (held from 19-20 June).

The 2003 World Games were the first to be held outside of the United States. Approximately 7000 athletes from 150 countries competed in the games in 18 official disciplines, and three exhibition sports. The participants from Kosovo were the region's first team at an international sporting event.

The opening ceremony hosted by Patrick Kielty featured an array of stars. The band U2 were a major feature, and Nelson Mandela officially opened the games.