Bone marrow transplantation, the goal which integrates hemato­ logists, immunologists, geneticists, oncologists and specialists of several other fields, has overcome its state of stagnation in recent years. Clinically as well as experimentally new approaches to old problems and new conclusions from recent findings proliferate: bone marrow transplantation in leukemic remission, bone marrow growth in cell culture, bone marrow manipulation with antisera, bone marrow differentiation in histoincompatible hosts, immuno­ suppression with partial body irradiation to cite just a few. These and other new developments were discussed by experts from 12 countries in and outside the European Community during an international seminar held on March 8-10, 1979 by