During the last few years, stereotactic radiosurgery has become a partner of equal rank within the discipline of neurosurgery. Today, it is regarded as being of the same importance as microsurgery and endovascular neurosurgery, branches which have also progressed rapidly in recent years. Breakthrough success, however, requires a combined effort of all partners involved. The editors of this volume have brought together contributions in the fields of neurosurgery, neuroradiology, neuropathology, neuroanatomy, radiation oncology and biophysics to discuss indications and therapeutic strategies in the treatment of arteriovenous malformations and intracranial tumours to find a common basis for future work.