Sixty-six of a series of 116 patients had a postural headache resulting from an inadvertent dural puncture (despite in 64 cases the provision of an epidural drip) and 50 had headache following a spinal block. Experience suggested that it is advisable to inject 20 ml of blood unless during the course of injection the patient complains of pain or discomfort. Blood should also be taken for culture. In only one patient (who had three dural punctures) of the 98 so treated has the patch failed to relieve the headache. Arguments are presented against the use of a prophylactic patch, and against utilisation of the epidural catheter as a route for injecting the patch.