Two cases of hypnotherapeutic treatment of psychogenic hyperhidrosis are presented. In both cases, organic aetiology could be excluded and conventional medical treatment modalities had no effect. In both cases, it was possible to modulate sweating in the trance state within less than a minute, thus supporting other reported cases of the effect of hypnotically induced modulation of autonomic responses. In the first case the psychological dynamics behind the physiological symptoms seemed unrelated to fundamental emotional and personal problems and relaxation and conditioning techniques in hypnosis had a positive effect in reducing the sweating to both objectively and subjectively socially acceptable standards. In the second case the hyperhidrosis was related to more fundamental personality problems and short term hypnotherapy proved ineffective in treating the condition.