We investigated the effectiveness of a special hypnotherapy technique in the treatment of chronic tension-type headache. A waitinglist control group was used to control for the changes in headache activity due to the passage of time. The results showed significant reductions in the number of headache days (p less than 0.05), the number of headache hours (p less than 0.05) and headache intensity (p less than 0.05). The improvement was confirmed by the subjective evaluation data gathered with the use of a questionnaire and by a significant reduction in anxiety scores (p less than 0.01).