The Sixth International Conference on Sintering and Related Phenomena took place at the University of Notre Dame, Notre Dame, Indiana June 6-8, 1983. This conference was also the twentieth Conference on Ceramic Sciences organized yearly by a "confederation" of four institutions: North Carolina University at Raleigh, N.C., the University of California at Berkeley, CA, Alfred University at Alfred, NY and the University of Notre Dame, Notre Dame, IN. The papers presented at the last Notre Dame conference collect­ ed in this volume, reflect the progress in our understanding of the process of sintering achieved in the past four years. It seems that the analysis of the two particle models is finally extended to the analysis of the models of compacts. In these investigations strong emphasis is put on pore-grain boundar­ ies interaction which appear to be central to this problem. It is to be hoped that in the near future an adequate model of the compact will be developed which may serve as a useful basis of powder tech­ nology. Also, the effects of atmosphere on the sintering of ceramics after a long period of neglect, seem to attract the attention of more workers in the field.