Intra-abdominal sepsis is a heterogeneous condition which in its severe forms carries a high mortality. The systemic consequences of established major infection are the result of a complex pathophysiology whose mechanisms are imcompletely understood. It is clear that early appropriate therapy is vital in minimizing effects of intra-abdominal infection and to this end early recognition of sepsis is important. Clinical examination may be unhelpful in difficult cases and special investigations may aid diagnosis; a high index of suspicion is mandatory. Surgery is the mainstay of therapy but may be inadequate and supportive measures are an essential adjunct.