Geotechnical works generally present complex engineering problems. The development of constitutive relations for geotechnical materials, with the help of numerical models, have increased notably the ability to predict and to interpret the mechanical behaviour of these geotechnical works. In this context, during the years 1988-1990, the Civil Engineering Department of the Catholic University of Rio de Janeiro, Brazil, the National Civil Engineering Laboratory of Lisbon, Portugal and the Faculty of Engineering of the University of Porto, Portugal have participated in a joint research project on the development and application of numerical models in geotechnical engineering. The first International Workshop on Application of Computational Mechanics in Geotechnical Engineering promoted by the above institutions and held at the Catholic University of Rio de Janeiro from 29 to 31 July, 1991, presented results of researches that were carried out during the collaboration project described above, as well as works of other well known researchers in the field, that were especially invited to participate in it.