We conducted a multicentre, randomized controlled trial with blinded outcome assessment. The treatment period was 6 weeks with follow-up assessment immediately thereafter and after 6 months. The objective was to determine the effectiveness of a craniocervical training programme combined with physiotherapy for tension-type headache. Eighty-one participants meeting the diagnostic criteria for tension-type headache were randomly assigned to an exercise group (physiotherapy and an additional craniocervical training programme) and a control group (physiotherapy alone). The primary outcome measure was headache frequency. Secondary outcomes included headache intensity and duration, Quality of Life (SF-36) and the Multidimensional Headache Locus of Control scale (MHLC). At 6 months’ follow-up, the craniocervical training group showed significantly reduced headache frequency, intensity and duration (P < 0.001 for all). Effect sizes were large and clinically relevant. Loss to follow-up amounted to 3.7%. Physiotherapy including craniocervical training reduces symptoms of tension-type headache significantly over a prolonged time frame.