PURPOSE OF REVIEW: This review highlights the impact of weight loss on metabolic dysfunction associated steatotic liver disease (MASLD), formally known as nonalcoholic fatty liver disease (NAFLD), and its progressive form of metabolic dysfunction associated steatohepatitis (MASH), formally known as nonalcoholic steatohepatitis (NASH). The effects of weight loss, as achieved through lifestyle modification, pharmacotherapy, bariatric surgery or endobariatric procedures on MASLD/MASH and hepatic fibrosis are discussed. RECENT FINDINGS: Although foundational in the treatment of MASLD/MASH, weight loss through life-style modification is challenging for most patients to achieve and sustain long-term. In patients with MASLD/MASH, a multidisciplinary approach may facilitate success with lifestyle modification, individualized consideration of pharmacotherapies and/or surgical approaches that have potential to lend an improvement in MASLD/MASH. Effective and sustained weight loss improves hepatic steatosis, steatohepatitis and potentially hepatic fibrosis. Improvement in hepatic fibrosis can improve patient-related outcomes associated with complications of advanced hepatic fibrosis or cirrhosis in patients with MASLD/MASH. Identifying risk factors that influence MASLD/MASH and early implementation of therapeutic weight loss strategies may improve chronic liver injury and decrease risk for adverse clinical outcomes related to progressive hepatic fibrosis attributable to MASLD/MASH.