Although drug-induced liver injury (DILI) is a rare clinical event, it carries significant morbidity and mortality, leaving it as the leading cause of acute liver failure in the United States. It is one of the most challenging diagnoses encountered by gastroenterologists. The development of various drug injury networks has played a vital role in expanding our knowledge regarding drug-related and herbal and dietary supplement-related liver injury. In this review, we discuss what defines liver injury, epidemiology of DILI, its biochemical and pathologic patterns, and management. (Hepatology Communications 2020;4:631-645). and Kidney Diseases established the U.S. DILI Network (DILIN) in 2003 to identify, enroll, and characterize cases of non-APAP DILI and herbal and dietary supplements (HDSs). (13) The U.S. DILIN has two registry studies at eight different academic centers across the United States. The network has expanded our understanding of DILI. Antimicrobials were noted to be the most common causative agents, accounting for 45% of cases in a 2004 study, followed by HDSs, cardiovascular drugs, central nervous system agents, antineoplastic agents, and analgesics. (14) Of the antimicrobials, amoxicillin-clavulanate (22%), isoniazid (11.7%), and nitrofurantoin (10.2%) were the top three implicated agents. (14) The network has also noted an increasing proportion of HDS-related liver injury,