Preliminary findings attesting to the successful therapeutic use of biofeedback training in reducing symptoms of chronic hyperhidrosis are reported. Eleven of the fourteen adult patients trained with biofeedback were able to demonstrate clinical improvement in their excessive sweating 6 weeks after termination of treatment. Relaxation was suggested as the active ingredient in the biofeedback treatment effect. These findings support a recent report of the successful use of biofeedback in treating patients with dyshidrotic eczema.