Depression is perceived worldwide as an important public health issue. Its prevalence has increased over the past 50 years. The reasons for the increase might be related, in part, to improved recognition and a greater willingness to label unhappiness or dysphoria as depression. Severe depression might be less amenable to prevention, although the identification of the stressors likely to trigger an episode in vulnerable individuals might prevent some recurrences. There is the potential, however, for the prevention of mild-to-moderate depression through action at the individual, community, and structural levels. This paper argues that nursing can make an important contribution to this prevention.At the individual level, this might be best accomplished through the development of the role of non-mental health nurses in primary care and workplace settings. At the community and structural levels, nursing as a profession can play an important role in influencing the commissioning of health care and the development of healthy public policy.