(Same as Epidemiology M203.) Lecture, three hours. Emphasis on methods that help to understand how systems operate and how to intervene on them. Exploration of how to characterize human-centered problems that arise, and how to handle complexity as core design and development challenge. Examination of different traditions of studying and modeling (representing) systems, both conceptually and quantitatively, to address questions that arise in public health. Consideration of utility and limitations of these methods for providing insight to stakeholders who are addressing population health problem. S/U or letter grading.