Opening Address.- to the Scientific Sessions. Accidents in Stereotaxy-Side-Effects or Bonus?.- Section I Epilepsy and Involuntary Movement Disorders.- Stereotactic Operations in Generalized Forms of Epilepsy.- The Role of the Cortex and Subcortical Ganglia in the Evoked Rhythmic Motor Activity.- Importance of the Cerebellar Hemisphere in Production of Tremulous Movement or Choreo-Dystonic Movement in Monkeys.- The Placement of Stereotactic Lesions for Involuntary Movements other than in Parkinson's Disease.- Stereotactic Operations in Cases of Hereditary and Intention Tremor.- Contributions to the Pathogenesis of Parinaud's Syndrome. Vertical Gaze Paralysis Following Bilateral Stereotactic Lesion in the Interstitial Nucleus Region.- Vestibular Function before and after Thalamotomy.- Post-Stereotactic Intracranial Haematomas.- Section II Hind Brain and Spinal Stereotactic Procedures.- Thalamotomy for Control of Chronic Pain.- Combination of Thalamotomy and Longitudinal Myelotomy in the Treatment of Multiple Sclerosis. A Case Report.- Protracted Long-Term Irradiation of Inoperable Midbrain Tumours by Stereotactic Curie-Therapy Using Iridium-192.- The Position and Extent of the Human Dentate Nucleus.- Physiological Guidelines for the Localization of Lesions by Percutaneous Cordotomy.- Physiological Correlates in Stereotactic Spinal Surgery.- A Stereotactic Approach to the Anterior Percutaneous Electrical Cordotomy.- Section III Surgery of the Pituitary Gland and Hypothalamus.- Pituitary Ablation by Yttrium-90.- Hypophysectomy - The Combined Role of Neuro- and Rhino-Surgeons.- Radiological Assessment of the Pituitary Gland.- Stereotactic Pituitary Implantation of Radioisotopes by Transfrontal Route. 300 Cases.- Stereotactic Thermal Pituitary Ablation.- Stereotactic Curie-Therapy of Pituitary Adenomas. A Long-Term Follow-Up Study.- Stereotactic Treatment of Craniopharyngiomas.- Stereotactic Hypothalamotomy in Erethic Children.- Section IV Stereotactic Techniques.- Stereotactic Radiosurgery in Intracranial Arterio-Venous Malformations.- A Versatile Stereotactic System Based on Cylindrical Co-Ordinates and Using Absolute Measurements.- Serial Stereotactic Biopsies.- A Simple Method for Obtaining Stereotactic Biopsies from the Human Basal Ganglia. A Case of Cerebral Porphyria.- Computer Display of Stereotactic Brain Maps and Probe Tracts.- The Use of a Small Digital Computer for Stereotactic Surgery.- Mathematical Models and Analogic Dosimetry on Phantom in the Interstitial Radiotherapy of Brain Tumours with "Gamma-Med".- Towards a Three-Dimensional Brain Model Stored in a Computer.