This text presents some of the subjects approched by the economic history group (XVIIthXXth centuries), under my coordination at the Laboratório Interdisciplinar de Pesquisa em História Social (LIPHIS) and the Programa de Pós-graduação em História Social (PPGHIS). We took a special attention to the following questions: the portuguese Empire, social hierarchy and chaning process in the colonial society. The article introduces some methodological problems and technics of research discussed by he group. Many of the ideas exposed are hypothesis of the researches in course.