The contributions published in this volume represent the outcome of a Seminar organized the 5th November 1990 in Vatican by the Pontifical Council for Justice and Peace in preparation of the centenary of the Encyclical Rerum Novarum. The aim of the Seminar was that of involving a group of worldwide distinguished economists in a frank and informal discussion on some aspects of the relation between ethical values and the economic reality that are considered particularly important for the social doctrine of the Church.