SINCE 1951, SCIENTISTS HAVE MET ON A BIENNIAL BASIS IN CHICAGO, ILLINOIS TO DISCUSS THE LATEST ADVANCES IN OUR UNDERSTANDING OF THE MICROBIOLOGY UNDERPINNING DIGESTIVE FUNCTION AND RUMINANT NUTRITION. WHILE FUNDAMENTAL QUESTIONS REGARDING ROLES OF MICROORGANISMS IN RUMINANT DIGESTION, AND FACTORS INFLUENCING THE EFFICIENCY OF RUMINANT DIGESTION AS A WHOLE REMAIN, NEW PROBLEMS AND CHALLENGES FACE ANIMAL AGRICULTURE. MANY OF THESE CHALLENGES AND ISSUES HAVE A MICROBIOLOGICAL CONTEXT, AND WILL BE BEST ADDRESSED BY INTEGRATIVE STUDIES IN MICROBIOLOGY, (IMMUNO) PHYSIOLOGY, AND NUTRITION. THE CALLS FOR FURTHER RESTRICTIONS ON ANTIMICROBIAL USE FOR GROWTH PROMOTION AND PROPHYLAXIS,PRE- AND POST-HARVEST FOOD SAFETY,AND THE IMPACT OF ANIMAL AGRICULTURE ON THE ENVIRONMENT ARE JUST A FEW EXAMPLES OF AREAS THAT WILL REQUIRE NEW LINES OF INVESTIGATION IN MICROBIOLOGY, (IMMUNO) PHYSIOLOGY, AND NUTRITION.TO ADDRESS THESE CHALLENGES,THE CONGRESS ON GASTROINTESTINAL FUNCTION (CGIF 2017) WILL BE HELD APRIL 19-21, 2021, AT THE GLEACHER CENTER IN DOWNTOWN CHICAGO. THE CONFERENCE IS COMPRISED OF TWO AND A HALF FULL DAYS OF PRESENTATIONS. THERE WILL BE SIX ORAL SESSIONS, EACH LAUNCHED WITH A PLENARY LECTURE FROM A PRE-EMINENT SCIENTIST IN GASTROINTESTINAL FUNCTION, WITH THE THEME OF MICROBIOLOGY AND NUTRITION. A SET OF INVITED PLENARY SPEAKERS HAVE ACCEPTED AN INVITATION TO SPEAK AT THE CONGRESS. WE ARE INTERESTED IN OBTAINING A BALANCE IN TERMS OF SCIENTIFIC FIELD AND TO THE EXTENT POSSIBLE, GENDER AND MINORITY ISSUES ACROSS THE SCIENTIFIC SESSIONS.