Of 80 depressed outpatients treated with either amitriptyline or amoxapine, 24 (30%) showed substantial clinical improvement within one week. Rapid responders were somewhat less depressed than non-rapid responders, had less emotional withdrawal, hostility or social-interpersonal disturbances, tended to be non-white, & felt more hopeful, useful, & needed before treatment began. The significance & possible mechanisms of the rapid response phenomenon are discussed.