The intention of social marketers, by definition, is to contribute to social good. However, an unintended consequence of the frequent use of fear-arousal in social marketing may be the creation of a sense of helplessness both in the target market and in unintended markets. Arousing fear may be counterproductive when attempting to persuade some people to abandon anxiety-soothing, addictive behaviours, such as smoking, drug and alcohol use (Firestone 1994) and may lead to counterproductive, fatalistic thinking and maladaptive responses (Job 1988; Rippetoe & Rogers 1987). The possibility that fear arousal creates helplessness is an important issue for marketing in the next millennium. Helplessness has been shown to be a major factor in depression (Seligman 1975) and depression is acknowledged by the World Health Organisation as one of the world’s primary health problems. The paper presents the case for appealing to positive motivations and emotions as a way to minimise the negative impact of using threat appeals in social marketing. A methodology for systematically testing the relative effectiveness of positive vs negative appeals is described.