In this issue of Clinics in Liver Disease, guest editor Dr. Zobair M. Younossi brings his considerable expertise to the topic of MASH/NASH Fatty Liver. With an estimated 115 million people worldwide affected by MASH, the disease burden casts a wide net:: many have other comorbidities, like diabetes, that make diagnosis and treatment critical. MASH-related liver cancer has increased 20% since 1990, and MASH is becoming a leading cause of liver transplants in adults, reflecting its significant impact on liver health. This issue provides state-of-the-art clinical reviews on MASH and NASH and also shines a light on the disease burden across the globe.