The work of nurses in managing and advancing population health is not complete without advocacy actions and contributions to policy making. This chapter focuses on the concepts, skills, and activities related to advocacy and policy making that are important to nurses to support and advance population health goals. Knowledge of the social determinants of health aids nurses in understanding the root causes of poor health among populations and provides guidance toward solutions. With nearly four million nurses in the United States, nurses’ civic engagement through the vote is a particularly powerful form of political participation that can have great influence over the direction of health policies. By using strong communications and advocacy skills, nurses can and should engage in advocacy and the policy process to improve the health of populations as part of their ethical professional promise to the people for whom they care.