Pseudomyxoma peritonei (PMP) is an uncommon clinical condition that typically originates from a perforated epithelial neoplasm of the appendix. The clinical presentation is variable, often with non-specific symptoms and is associated with abdominal distension in advanced cases. Whilst traditionally considered benign, it is apparent that PMP represents a spectrum of disease and, at best, should be considered a "border-line" malignancy. The condition is characterised by the development of mucinous ascites. Tumour cells and mucin accumulate at characteristic sites within the peritoneal cavity according to the redistribution phenomenon, usually sparing the mobile small bowel. In advanced cases, high volume disease and mucinous ascites lead to compression of the gastrointestinal tract, bowel obstruction, and ultimately, starvation. Controversy still exists over the pathological classification of PMP and its prognostic value. Computed tomography remains the optimal preoperative staging investigation. Elevation of serum tumour markers correlates with a worse prognosis. Optimal treatment involves cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). With complete cytoreduction and HIPEC an 80% 5 year survival can be achieved in patients with low grade disease. Maximal tumour debulking can produce good palliation and long term survival in a small number of patients. Initial high morbidity and mortality is seen to decrease with increasing experience and this is likely to represent improvement in patient selection and postoperative management as well as surgical expertise.