This volume of Advances in Neurosurgery 7 presents the papers held at the Joint Meeting of the American Academy of Neurological Surgery and the "Deutsche Gesellschaft fUr Neurochirurgie" in October 1978 in Munich. This exchange of thoughts on scientific methods in neurosurgery on both sides of the globe, i.e., both in the United States and in Germany, covered a number of different topics in the field of neurosurgery, with special emphasis on the following subjects: Intracranial vascular surgery and specialized neurosurgical techniques used for different operative approaches to the skull, brain, pituitary gland, and peripheral nerves. Contributions to the field of computer tomography, traumatology, functional and experimental neurosurgey, as well as chemotherapy rounded off the broad exchange of thoughts. In particular, the variety of the problems discussed, gives insight into the present state of our special field and shows progress and new points of departure. Special gratitude is expressed to the Springer-\Tedag for its help in editing the Ad vances in Neurosurgery, Volume 7. Miinchen, September 1979 EMARGUTH v Opening Oration F. MARGUTH I should like to welcome all of you wholeheartedly to the Joint Meeting of the American Academy of Neurological Surgery and the Deutsche Gesellschaft fUr N eurochirurgie. I welcome especially our collegues from the United States and the ladies.