Pseudomyxoma peritonei involves the gradual accumulation of gelatinous peritoneal metastases, typically resulting from the rupture of a mucinous appendiceal neoplasm. Standard treatment often includes cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. However, recurrence is common despite optimal cytoreduction, prompting ongoing investigation into novel therapies. This comprehensive review aims to enhance radiologists' understanding of mucinous appendiceal neoplasms and pseudomyxoma peritonei by focusing on nomenclature, pathophysiology, optimal imaging strategies, and the typical imaging appearance of mucinous appendiceal neoplasm and associated peritoneal disease. It also highlights problematic areas of disease that may affect the ability to achieve complete cytoreduction or influence surgical decision making and includes a surgeon's perspective on treating this complex condition.