Statement of the Problem . . . Latin America In Latin America and specifically in Chile the most dynamic (socially concerned) clergy have experienced the phenomenon of secularisation in a way that is perhaps different from the clergy in Europe or the United States. In these countries the strongest impact has probably been made by the scientific and technical discoveries of recent years. On the other hand, in Latin America the impact is felt especially through the experience of the power of mass movements to produce cultural transformations which pastoral action has never been able to bring about. These mass movements have become a reality, thanks to leaders, generally non-Christian, who understood and could make use of socio-economic and sociopolitical laws which allowed radical changes in structures of exploitation. Seeing the effectiveness of these mass movements and technical expertise of their leaders, some of the clergy became increasingly conscious of the contrast with the more or less total failure of large scale ecclesiastical pastoral action such as Catholic Action, Y.C.W, Y.C.S, the Christian Family Movement... etc. I believe that this feeling of frustration built up within the clergy a sense of inferiority and ineffectiveness which today appears as their major problem. What social changes had the Church been able to achieve in Latin America, bearing in mind that 99% of the people are baptized, that is to say are people who might be expected to respond to the directives of the ecclesiastical leaders? It is this uncomfortable feeling that has pushed the progressive clergy to look for new forms of theological understanding that will promote really effective Christian thinking on the radical transformation of the structures of exploitation. This is where we find the psychological roots of action and indeed the theological roots too, for the breath of the Spirit can surely be felt there.