While knowledge represents a valuable commodity, not all forms of knowledge are afforded equal status. The politics of knowledge, which entails the privileging of particular ways of knowing through linkages between the producers of knowledge and other bearers of authority or influence, represents a powerful force driving knowledge development. Within the health research and practice community, biomedical knowledge (i.e. knowledge pertaining to the biological factors influencing health) has been afforded a privileged position, shaping the health research and practice community's view of health, illness and appropriate intervention. The aim of this study is to spark critical reflection and dialogue surrounding the ways in which the politics of knowledge have constrained progress in addressing mental health and illness, one of today's leading public health issues. I argue that the hegemony of biological knowledge represents an ethical issue as it limits the breadth of knowledge available to support practitioners to ‘do good’ in terms of addressing mental illness. Given the power and influence inherent within the nursing community, I propose that nurses ought to engage in critical reflection and action in an effort to better situate the health research and practice community to effectively address the mental health of populations.