Ulcerative colitis (UC) is a chronic and relapsing inflammation limited to the colonic mucosa and always involving the rectum with variable extension towards the cecum. The aim of medical treatment is to induce and maintain clinical remission. In contrast to Crohn's disease for which a 'top-down' or 'early aggressive' therapy is discussed, in UC the concept of a step-up treatment is still valid. This step-up approach includes local or systemic administration of 5-aminosalicylic acid as first-line therapy followed by topical or systemic steroid administration as well as azathioprine, 6-mercaptopurine, cyclosporine, and more recently anti-tumor necrosis factor monoclonal antibodies as options in refractory or chronic active disease. Colectomy may be necessary if medical treatments are unsuccessful or if complications develop. The decision about the individual therapy of UC is dependent on both disease activity and on disease location. Different therapy strategies are applied in ulcerative proctitis, left-sided colitis, pancolitis and fulminant colitis as well as in chronic active disease and maintenance of remission. This overview presents important concepts in the treatment of UC based on the published guidelines.