The Third International Conference on Lymphatic Tissue and Germinal Centers in Immune Reactions was held at the University of Uppsala in Sweden, September 1-4, 1970. The conference is obliged to Professor K. E. Fichtelius for his initiative in establishing the meeting, as well as for the assistance of his staff at the Department of Histology in organizing the meetings. At the University of Uppsala inquiries into the lymphatic system go back to the 17th century and are marked by milestones, such as Olof Rudbeck's discovery of the thoracic duct in 1651 and August Hammar's fundamental work on...