ALHSUD has its origin in the Latin American hydrogeologists meeting held in Cochabamba (Bolivia) in 1987, specified after the Second Latin American Conference on Urban Hydrology (Buenos Aires, November 1989). Its first president (reelected) was Prof. Dr. Aldo Reboucas (Brazil), who served until 1999, going to perform it after the Assembly election in Montevideo (November 1998) Prof. Dr. Mario A. Hernandez (Argentina) until September 2006, when he assumes the current president Dr. Jorge Montaño (Uruguay).