A study into the neurosurgical approach to thirty-five patients with increased intracranial pressure due to inflamatory diseases affecting the central nervous system and meninges is reported. The entities under consideration were found to have similar surgical aspects despite the heterogeneity of etiologic agents. As regards the surgical treatment, two groups of cases were recognized. Group 1 comprises 7 patientes with symptoms of a space-occupying lesion; in these patients craniotomies were perfomed with good results. Group 2 included the remainder 28 cases with acquired hydrocephalus. In this group differents methods for ventricular drainage were used, but ventriculo-auriculostomy and specially ventriculo-peritoneal shunts proved to give more gratifying results. Chemotherapy was administred when the etiologic agent was disclosed. Corticosteroids were institued to reduce inflammatory reations and cerebral edema. A review of the literature supported the practical classification and surgical techniques employed.