The management of Crohn's disease and ulcerative colitis has become increasingly complex. With the current utilization of immunosuppressive therapies earlier in the disease course for patients presenting with moderate to severe disease, there is a great need for additional biologic agents targeting inflammatory mediators other than anti-tumor necrosis factor-α (anti-TNF) agents. Although anti-TNF agents have positively impacted the treatment of inflammatory bowel disease, many patients can lose their response or develop intolerance to these agents over time through the formation of antidrug antibodies. Furthermore, a sizeable percentage of patients are primary nonresponders to anti-TNF drugs. Vedolizumab (Entyvio, Takeda Pharmaceuticals), a monoclonal antibody to the α4β7 integrin, inhibits gut lymphocyte trafficking and has been demonstrated to be an effective and safe agent for the treatment of both Crohn's disease and ulcerative colitis. This article reviews the clinical trial evidence and rationale for the use of vedolizumab in moderate to severe Crohn's disease and ulcerative colitis.