The purpose of this discussion paper is to explore how nurses can be strategically poised to advocate for needed policy change in support of greater income equality and other social determinants of health. We adapted Bronfenbrenner's social‐ecological model to highlight how four broad pervasive subsystems shape the opportunities that nurses have to engage in advocacy at the policy level. These subsystems include organizations (the microsystem), professional bodies (the mesosystem), public policies (the exosystem), and societal values (the macrosystem). On the basis (...) of this adapted model, we recommend changes among modifiable elements of the microsystem and mesosystem that can help position nurses (ecologically and collectively) to advocate for public policy change and use examples from a Canadian context to illustrate these points. We believe that the ideas arising from this model can be widely used where policy action on the social determinants of health is needed to inform, guide, and frame change efforts and advocacy work. (shrink)