Like all other organisms, pathogens are in an ongoing ecological and evolutionary struggle for existence. However, how this struggle unfolds can have tremendous impacts for human health. We will focus on understanding fundamental processes in ecology and evolution that drive pathogen emergence, spread, and evolution in populations. We will also discuss how our understanding of ecology and evolution has lead to breakthroughs in treatments and management strategies across healthcare, agriculture, and beyond (i.e., vaccinations, cocktail therapy, crop diversification).