Mucosal prolapse solitary rectal ulcer syndrome is a condition which has frequently confused both pathologists and surgeons alike. Despite its recognition in the nineteenth century, it continues to be a diagnostic challenge. The significance of correctly diagnosing this condition is that it avoids the morbidity and mortality associated with major surgery or the side-effects of long-term medical treatment. This review considers the histological features of mucosal prolapse and how it may mimic other pathological conditions.