Public health is a multidisciplinary field that is difficult to define and has multiple definitions which are still evolving. Having a scientific basis for the practice of public health is critical. Research leads to insight and innovations that solve health problems and is therefore central to public health worldwide. The objective of public health research is to use the knowledge gained to propose policies and interventions, based on scientific evidence, and to help improve the health and well-being of the population and ultimately reduce/eradicate health inequalities. Public health research is characterized by its multidisciplinary approach. It draws on several disciplines in its development and management, especially epidemiology/human ecology; biostatistics; physical and social sciences as applied to health; biology; genetics; and toxicology. The chapter gives an introduction on public health and its history. It also talks about the importance of research in public health and outlines the various methods used in public health research.