This chapter discusses Crohn’s disease (CD). A typical scenario will be a patient presenting to the Emergency Department with abdominal pain and diarrhea, but patients may also present with stricturing or fistulizing disease. Frequent findings on history and physical exam of patients with CDs are discussed, as well as differential diagnoses, work-up, treatment, outcomes, complications, common curveballs, and clean kill questions pertinent to the oral boards.