Mucocoele of the appendix occurs when obstruction of the appendiceal lumen results in mucus accumulation and consequent abnormal dilatation. The most important aetiology, from a surgical perspective, is either mucinous cystadenoma or cystadenocarcinoma. In the latter, a spontaneous or iatrogenic rupture of the mucocoele can lead to mucinous intraperitoneal ascites, a syndrome known as pseudomyxoma peritonei. Optimal management of mucoceles is achieved through accurate preoperative identification and subsequent careful resection. We report two cases and subsequently discuss the clinical presentation of mucocoeles, their association with pseudomyxoma peritonei and an optimal management of both conditions.