This volume of ADVANCES IN NEUROSURGERY presents the original texts of 60 papers delivered at the 33rd annual meeting of the German Neuro- surgical Society held in Kiel from May 16th to 20th, 1982. These papers represent a selection from some 162 papers submitted and 96 actually given. The selection was made by the society's programme committee, of which Professor W. J. BOCK, Professor H. DIETZ and Professor W. GROTE are also members. I would like to take this opportunity to express my sincere thanks to them for their untiring cooperation. The scientific programme dealt with three main themes: 1. Acute, non-traumatic intracranial hemorrhages, a subject that has always been of importance for neurological surgeons since the ana- tomist Giovanni Battista MORGAGNI in 1791 first described in detail the clinical picture and the pathological and anatomical causes of a brain hemorrhage he had observed in his servant. Indeed, at our 31st annual meeting in Erlangen in 1980 "e;Timing Problems in Sub- arachnoid Hemorrhages"e; was one of the main topics of discussion. For this year's meeting a cooperative study in which 27 university and hospital departments of neurosurgery participated enabled us to look into the causes and the diagnostic and therapeutic measures involved in a great number of cases of intracranial hemorrhage.