Advances in axon biology are so rapid that every year provides us with a wealth of new facts and observations; hence, this conference cannot reasonable be expected to answer all questions. Rather, its purpose must be to take stock of the available data, to communicate advances and new concepts, and to help us to formulate the goals and approaches for future research. To this end, ample time was allotted during the symposium for discussion, but these exchanges of thoughts cannot, unfortunately, be included in the printed text. We hope that publication of the presentations will provide a valuable source of information on the present state of knowledge on this most important borderland between neuro pathology, neurophysiology and neurochemistry. We would like to express our gratitude to all participants of the symposium for contributing their efforts and for their enthusiasm. We are also indebted to Springer Verlag and Bergmann Verlag for publication of the symposium and for their appreciation of the editorial concerns.