Frontotemporal brain sagging syndrome is a dementia associated with hypersomnolence, personality changes, and features of intracranial hypotension on magnetic resonance imaging. The literature is sparse with respect to treatment options; many patients simply worsen. We present a case in which this syndrome responded to lumbar dural reduction surgery. Postoperative magnetic resonance imaging indicated normalization of brain sagging and lumbar intrathecal pressure. Although no evidence of cerebrospinal leak was found, extremely thin dura was noted intraoperatively, suggesting that a thin and incompetent dura could result in this low-pressure syndrome. Clinicians who encounter this syndrome should consider dural reduction surgery as a treatment strategy.