A post-dural puncture headache is a potential complication of a lumbar puncture. Physicians should be able to readily diagnose and treat this potential complication. Described here is a patient who developed an unresolving post-dural puncture headache that then developed into a subdural hematoma. A subdural hematoma is a rare complication following lumbar punctures. Unresolving headaches following a lumbar puncture should prompt aggressive investigation.