The Monks of Athos in Greece constitute a particular group with unusual sleep schedule and specific diet. In order to study the frequency of headache among them, a special questionnaire was designed. Four hundred forty-nine monks below the age of 50 were approached, 39 of whom suffered from frequent (more than one episode per month, in the last 6 months) headaches (8.68%). The prevalence of migraine was 1.78% (0.66% with aura and 1.11% without) and of tension-type headache 3.34% (1.33% chronic and 2% episodic). Furthermore, 1.87% of monks suffered from mixed headaches (tension-type and migraine attacks as well). Cluster headache was not traced.