Background: Subdural hematoma (SDH) is a serious complication of shunt surgery for normal pressure hydrocephalus (NPH). Since the introduction of adjustable valves, management strategy has changed significantly. Methods: A retrospective review of NPH patients treated in the Hydrocephalus and CSF Disorders Clinic over the past five years was conducted. A review of clinical materials and imaging identified 32 patients who developed SDH following shunt surgery for NPH. Results: Twenty-seven patients were male and five were female. Mean age was 74. All patients received programmable valves. Nineteen patients were diagnosed with SDH within six months of shunt insertion, with a mean duration to diagnosis of 48 days. Five required surgery. The remaining 14 patients were treated successfully with shunt adjustment. All patients returned to their clinical baseline. Thirteen of the 32 patients developed SDH after a period of six months, with a mean duration to diagnosis of 43 months. None required surgical intervention. Ten patients were treated with shunt adjustment. The remainder were observed. Conclusions: Close surveillance following shunt insertion, particularly within the first six months post-op, is essential to prevent significant clinical sequelae secondary to SDH. Programmable valves can play an important role in early SDH management.