Maurice Ravel had been subject to psychiatric disorder for many years when signs of organic brain disease appeared at the age of 52. Aphasia, apraxia, agraphia, and alexia became established some five years later. Musical creativity was lost. Alajouanine diagnosed cerebral atrophy with bilateral ventricular enlargement. Though Ravel's condition deteriorated progressively, generalised dementia was not apparent. He died in December 1937, after a craniotomy performed by Clovis Vincent, possibly from a subdural haematoma. Vincent's operative findings are described here. The likely cause of Ravel's illness was a restricted form of cerebral degeneration.