This review focuses on the impact and effectiveness of intersectoral action in public health practice on the social determinants of health and health equity. Additionally, the review identifies gaps in current research on and documentation of effective public health practice. A recent systematic review on the impact on health of collaboration between local health service organizations and local governments did not assess the impact on health equity. To our knowledge, the current report represents the first attempt to systematically assess the impact of intersectoral action in public health on the social determinants of health and health equity using literature from a number of countries. This review examines the question, “What is the impact and effectiveness of intersectoral action as a public health practice for health equity through action on the social determinants of health?” The review also explores two additional questions: What is the role of the public health sector in intersectoral action on the social determinants of health for health equity? What tools, mechanisms, and strategies support the initiation and implementation of intersectoral action to improve health equity?