The Institute of Group Analysis has run training schemes in group psychotherapy for a number of years. The Introductory Group Work Course was modified some five years ago to include a large-group experience in the third and final term. Large groups are frequently employed as part of the therapeutic organisation of institutions. It is arguable whether they are most valuable in the realm of sociotherapy or psychotherapy. Training groups encourage the increase of personal awareness and insight through the techniques of feedback and the exploration of group dynamics. Political transactions, both nationally and internationally, so often take place in a large-group setting. The powerful forces of the large group must be acknowledged and respected, because of their potential use for either good or evil. The capacity of the large group to regress into a dependent relationship necessitates a degree of integrity in the leadership of the group.