The clinical presentation of chronic post-traumatic headache in 53 patients from a highly specialized headache clinic was analysed and classified according to the diagnostic criteria of the primary headaches in The International Headache Classification 2nd Edition, and compared with the 1st Edition. All patients fulfilled the criteria for both editions indicating that the restrictions in the 2nd Edition have no major influence on the prevalence in specialized clinics. We found the phenomenology to be very heterogeneous, but the vast majority (77%) of patients presented with headache resembling chronic tension-type headache, either as the only manifestation or in combination with migraine symptoms. For the first time episodic tension-type headache is described as occurring after head trauma. The prevalence of coexisting analgesic overuse was 42% and the treatment outcome for these patients was just as favourable as in primary headaches, whereas the time-consuming multidisciplinary treatment demonstrated only very modest results.