Public health activity, and the state’s public health responsibilities to assure the conditions in which people can be healthy, can only be achieved through different means of social coordination. This places law and regulation at the heart of public health. They are fundamental both to methods of achieving public health goals and to constraints that may be put on public health activity. As such, trainees, practitioners, and leaders in public health need to understand the breadth and nature of wide-ranging legal and regulatory approaches and the place of ethics in public health.