The burden of digestive diseases in the United States is staggering, with annual costs exceeding $140 billion, based on National Institutes of Health (NIH) estimates. To meet this challenge, a key mission of the National Institutes of Diabetes and Digestive and Kidney Diseases (NIDDK) is to support the training of a talented, diverse pool of young investigators who will attack scientific unmet needs to improve the lives of patients with gastrointestinal and liver diseases. The Icahn School of Medicine at Mount Sinai (ISMMS) has been a center of excellence for care in gastrointestinal and liver diseases for decades, with clinical fellowship programs in these disciplines consistently ranked among the best in the country. Moreover, ISMMS offers a fertile environment from which a cadre of outstanding candidates have launched successful careers in academic gastroenterology and hepatology. The overarching goal of this Training Program proposal is to leverage this outstanding environment to support the training of M.D., M.D./Ph.D or Ph.D. postdoctoral fellows by providing exceptional research opportunities and mentorship in three broad areas: A) Gastrointestinal inflammation and the microbiome; B) Non-alcoholic steatohepatitis (NASH), hepatic inflammation and fibrosis; and C) Genetics of gastrointestinal and liver diseases. The highly structured training program provides a tailored curriculum that integrates clinico-epidemiologic-, genetic-, environmental- and cellular/molecular research excellence. The program is built upon a foundation of world class research faculty who have outstanding track records of academic achievement and successful mentorship. The curriculum focuses on cross-disciplinary training in order to prepare trainees for the current and future challenges of gastrointestinal and liver disease research, which now requires integration of complementary research skill sets. To address this need, a highly selected pool of mentors has been chosen not only from within the Divisions of GI and Liver Diseases and other clinical disciplines, but who also represent outstanding multi-disciplinary institutes at the ISMMS. Each year this program will support 3 trainees (PGY 4 - PGY 6), with 15 candidates entering the program over 5 years. Each trainee will pursue an individualized research project and tailored curriculum formulated together with their primary and secondary mentors, curriculum committee and the Program Directors. Trainees will dedicate at least 90% effort in either the laboratory or clinical setting, and their progress will be monitored through quarterly meetings with their advisory committee and program directors. Overall quality and adaptability of the program will be ensured through oversight by internal and external advisory boards, based on compliance with defined metrics of success for both individual trainees and the overall program. This rigorously structured and closely monitored program, committed to excellence and built upon...