This year, Brazil celebrates its 500 years of discovery. To mark this great event, the Brazilian Arti cial Intelligence (AI) community organized a special int- national joint conference putting together SBIA 2000 (the Brazilian AI Sym- sium) and IBERAMIA 2000 (the Ibero-American AI Conference). SBIA 2000 is the 15th conference of the SBIA conference series, which is the leading conference in Brazil for presentation of research and applications in Arti cial Intelligence. Since 1995, SBIA has become an international conference, with papers written in English, an international program committee,...