In this issue the paper by Cumurciuc et al¹ (pp 1084–7) reports 17 cases from 123 consecutive patients with cerebral venous thrombosis (CVT) in whom the only neurological sign was headache. The series is biased by the fact that the Department of Neurology of the Lariboisiere Hospital in Paris has particular competence both in headache and stroke, and runs an emergency headache centre where patients can consult a headache specialist without long waiting times. What are the lessons to be learned from this …