Diverticular disease produces a wide range of clinical presentations varying from minimal clinical discomfort to life-threatening complications. Often there is a considerable discrepancy between clinical, radiologic, endoscopic and pathologic findings. Diverticulosis is a quite common disease affecting about 2/3 of people in the Western world over the age 80. The exact incidence of acute diverticulitis is unclear. We distinguish between uncomplicated and complicated diverticular disease forms. The latter includes abscess formation, stricture, obstruction, and free perforation causing life-threatening peritonitis. Several classifications for perforated diverticulitis have been proposed. From the practical point of view the Hansen-Stock classification seems to be the most appropriate one as it includes all forms of diverticular disease; it can also be used preoperatively. Prophylactic resection to avoid complications is not justified in minimally symptomatic individuals. Timing of the operation depends on the clinical course and the grade of peritonitis and on concomitant treatment modalities. Emergency operations should be avoided if possible, to reduce morbidity and mortality. Elective operations should be performed best 6-8 weeks after a second diverticulitis attack. Resection plus primary anastomosis is preferred to a Hartmann?s procedure, if possible. Elective surgery should be done laparoscopically. In acute diverticulitis the goal is to treat uncomplicated forms conservatively, while complicated forms should undergo elective, laparoscopic colon resection.