1. Connective tissue massage produces relief of pain and increases microcirculation in a number of vascular beds. 2. The concentration of plasma beta-endorphins has been measured in 12 volunteers before and 5, 30 and 90 min after a 30-min session of connective tissue massage. 3. There was a moderate mean increase of 16% in beta-endorphin levels from 20.0 to 23.2 pg/0.1 ml (P = 0.025), lasting for about 1 hr with a maximum in the test 5 min after termination of the massage. 4. It is assumed that the release of beta-endorphins is linked with the pain relief and feeling of warmth and well-being associated with the treatment.