Forty patients with tension headache and 40 healthy comparable control persons were palpated by the same “blinded” observer. Tenderness in 10 pericranial muscles on each side was rated on a four-point scale. A Total Tenderness Score was calculated for each individual by adding the scores from all palpated areas. Headache patients had significantly higher scores than controls and also significantly higher tenderness in each point separately. Median normal values and confidence limits for tenderness are given. Among 23 patients with daily headache a correlation was found between headache intensity and Total Tenderness Score. It is likely that the pathologic tenderness in patients with tension headache is the source of nociception, but pain mechanisms are more complex, as evidenced by discrepancy between tenderness and pain in some patients. Pathologic tenderness should be a contributing criterion to the diagnosis of tension headache (muscle conctraction headache).