The Training School provides an introduction to burden of disease assessment, using COVID-19 as a case study. The TS will provide public health professionals, and researchers from related fields, with practical knowledge about summary measures of population health, the historical background of the Global Burden of Disease study and its outputs. Furthermore, the TS will introduce the concept and rationale of the main metrics (YLLs, YLDs and DALYs), and underlines their application and importance or priority setting in public health policy and decision-making processes.