Normal-pressure hydrocephalus (NPH) is an uncommon condition in which the cerebral ventricles enlarge, even though pressure within the skull remains normal. Most patients develop this in their 70s, and symptoms include some combination of cognitive impairment, difficulty walking, and urinary incontinence. The diagnosis is based on a combination of clinical criteria and findings on brain imaging. Some patients benefit from shunting (usually ventriculoperitoneal shunting). Not all patients are good candidates for this procedure.