The case of a 39-year-old with intractable spontaneous intracranial hypotension (SIH) is presented. He developed bilateral and symptomatic subdural hygromas that were drained in response to clinical deterioration, but proved ineffective. An initial MRI of the lumbar region suggested a lumbosacral CSF leak, but he failed to respond to local blood patching. Subsequent CT myelography revealed a thoracic dural leak and a second directed blood patch proved effective. The aetiology, pitfalls and management of SIH are summarized.