This volume represents the Proceedings of the VI International Conference on Lymphatic Tissues and Germinal Centers in Immune Reactions. The meeting took place in Damp, a small resort with great facilities on the shores of the Baltic Sea near Kiel on June 11 - 16, 1978. Both, the Genius loci and the God of Weathers were charming enough to stimulate the many participants from all continents and also to facilitate the establishment and/or maintenance of close contacts outside the sessions. The organizers of this Conference have tried to remind the scientific community of the necessity to (re-) consider sufficiently the role of morphological studies for a thorough understanding of immune reactions. Furthermore, they have been anxious to emphasize a closer connection between analytical work and biological relevance of the phenomena observed. Thus, three main trends were formulated: (1) connections and correlation's between function and structure, (2) in-vivo relevance of in-vitro models and (3) clinical relevance of experimental models. The programme, induced by these outlines and reflected by the contents of this volume, covers a remarkably broad field of interests and activities. It is set in order under nine session chapters. Each of them may allow the reader to answer for himself the question how far the above trends have been recognized, especially when considering the variety of new methodological approaches reported. Although the usefulness of publishing proceedings such as these has sometimes been challenged, it is believed that the present volume provides a variety of stimuli for future experimental and clinical work on the function and structure of the immune system. Considering that scientific progress depends on both the generation of falsifiable hypotheses and the dissemination and experimental analysis of these, it is hoped that these proceedings will make a worthwhile contribution to these objectives.