Neurosurgery is a very different surgical specialty from the days when this investigator was a research fellow and resident in the years 1957 through 1967. Technological advances have enabled most of these changes from an almost brutal surgical specialty with many poor results to a field wherein a normally sensitive human being can work happily and effectively. These advances, “the four factors,” include application of the binocular dissection microscope to surgery, clinical neurophysiology, neuroradiology imaging, and neuroanesthesia. These advances were all necessary for the work to be described below. Two other important applications of technology but not used here include advances in stereotactic surgery (i.e., focused irradiation) and endovascular techniques. Utilization of these four factors has enabled us to see and do things hitherto thought impossible or at least highly dangerous.