The diagnosis and management of chronic diverticulitis, also commonly referred to as smouldering diverticulitis, remains a challenging topic for surgeons and gastroenterologists alike. Traditionally, diverticulitis has been classified as either uncomplicated or complicated. This rather simplistic view, however, has been called into question with the increasing recognition of several variations in clinical presentation, such as smouldering diverticulitis, which do not fit the traditional mold. This chapter will focus on the definition, pathophysiology, and management of smouldering diverticulitis.