Mary E. Rinella, Frank Tacke, Arun J. Sanyal, Quentin M. Anstee, on behalf of the participants of the AASLD/EASL Workshop – 9 July 2019 – Nonalcoholic fatty liver disease (NAFLD) is a global public health concern. Its natural history, the development of nonalcoholic steatohepatitis (NASH) and fibrosis, is highly variable, prone to endogenous (e.g., genetics, microbiota) and exogenous (e.g., nutrition, alcohol, physical activity) disease modifiers, and can fluctuate over time. The complexity of its pathophysiology is reflected by the multitude of pharmacological targets in development.