OBJECTIVE: To estimate the 1-year prevalences of migraine and tension-type headache (TTH), and identify their principal risk factors, in the general population of the Republic of Georgia. METHODS: In a community-based door-to-door survey, 4 medical residents interviewed all biologically unrelated adult members (>/=16 years) of 500 adjacent households in Tbilisi, the capital city, and 300 in rural Kakheti in eastern Georgia, using a previously validated questionnaire based on International Headache Society diagnostic criteria. RESULTS: The target population included 1,145 respondents, 690 (60%) women, mean age 45.4 +/- 12.0 years. The 1-year prevalences were as follows: migraine 6.5% (95% confidence interval 5.0-7.9), probable migraine 9.2% (7.5-10.8), all migraine 15.6% (13.5%-17.7%), TTH 10.0% (8.2-11.7), probable TTH 27.3% (24.8-29.9), all TTH 37.3% (34.5%-40.1%). Female gender and low socioeconomic status were risk factors for migraine but not for TTH. Headache on >/=15 days/month was reported by 87 respondents, a prevalence of 7.6% (6.1-9.1). Female gender, low socioeconomic status, and frequent use (>/=10 days/month) of acute headache drugs were risk factors. The likely prevalence of medication overuse headache was 0.9% (0.3-1.4), of chronic migraine 1.4% (0.7-2.1), and of chronic TTH 3.3% (2.3-4.4), but caution is needed in interpreting these estimates. CONCLUSIONS: While the prevalences of migraine and tension-type headache are comparable with those in Europe and the United States, a remarkably high percentage of the population of Georgia have headache on >/=15 days/month. This study demonstrates the importance of socioeconomic factors in a developing country and unmasks the unmet needs of people with headache disorders.