Abstract: An apparatus (10) for modifying undesired behaviors in humans who have undergone one or more hypnotherapy sessions to implant positive and aversive posthypnotic suggestions which are to be elicited in response to corresponding detected trigger events. In a preferred embodiment, the apparatus is a watch (30) and includes signal generators (15, 16, 19, 20) which are controlled by a processor (12) to generate tactile, visual and/or audio active signals that trigger positive and aversive posthypnotic suggestions. The apparatus is programmed to randomly generate a plurality of positive active signals during a period of time programmed by the subject. Additionally, manual controls (14, 18) are provided to allow the subject to selectively activate the positive active signals or negative active signals as needed.