This paper focuses on the need to advance legal terminology and terminography theory andpractice in the South Market. Considering the close relationship between law and language, a brief overviewof the linguistic panorama of multinational communities where similar studies have been developed issketched. The fallacy that there are no translation problems between Portuguese and Spanish is discussed aswell as the misleading idea of the equivalence of the national legal systems of the member countries.Theoretical and methodological assumptions viewing an approach specifically designed are examined. Thevalue of computerized resources the implementation of terminography is highlighted. Some ideal features forthe South Market terminographical production are outlined.