PURPOSE: To determine the clinical results in an unselected group of consecutive patients with osteoid osteoma treated with thermocoagulation. MATERIALS AND METHODS: In 97 consecutive patients with clinical and/or radiologic evidence of osteoid osteoma at any location, the clinical symptoms were assessed before and after thermocoagulation with computed tomographic guidance. A good response was defined as disappearance of symptoms that were manifested at presentation and attributed to osteoid osteoma. Clinical assessment was performed prior to discharge; within 2 weeks after the procedure; and at 3, 6, 12, and 24 months follow-up. After 24 months, a postal questionnaire was used for assessment. RESULTS: The mean clinical follow-up after the only or the last thermocoagulation session was 41 months (range, 5-81 months). Response was good after one session of thermocoagulation in 74 (76%) of 97 patients, and the 95% CI was 68% to 85%. Patients with persistent symptoms did well after repeated thermocoagulation (good response in 10 of 12 patients), but results of repeated thermocoagulation were poor in patients with recurrent symptoms (good response in five of 10). The overall success rate after one or two thermocoagulation procedures combined was 92% (89 of 97 patients), and the 95% CI was 86% to 97%. Complications were observed in two patients. CONCLUSION: Percutaneous thermocoagulation is a safe and effective method for treatment of osteoid osteoma at any location. Repeated thermocoagulation is successful in patients with persistent symptoms.