We report here the results obtained thus far along two distinct but complementary and converging lines of research work. The theme is conceptual data base design (specification), and the work has been going on for a number of years, mainly at the University of Stuttgart, in the Federal Republic of Germany, and at the Pontificia Universidade Cat6lica do Rio de Janeiro, in Brasil. We are glad to acknowledge the collaboration of several colleagues and students, particularly H. Biller, J. M. V. de Castilho, A. Horndasch, C. S. dos Santos, R. Studer, U. Schiel, and I. Waiter. Two other co-workers...