In this module, we will discuss chronic diarrhea. You will learn how to diagnose the cause of chronic diarrhea through the more widely used anatomical approach. In particular, you will learn to differentiate between small bowel process, large bowel process, and steatorrhea, through a complete history, physical exam, and investigations. Finally, you will learn how to properly treat conditions such as celiac disease, ulcerative colitis, Crohn’s disease, and irritable bowel disease.