The inverted polypoid hamartoma of the rectum (IPHR) is characterized by polypoid masses composed of ectopic glands of Lieberkühn invaginated within the mucosal muscle to form a conglomeration in the submucosa, hence the term "inverted polyp". It produces an unremarkable rectal syndrome, more suggestive, when abundant glairy exudate is observed, in young subjects. It causes a unique sessile polypoid lesion, occasionally multilobular or a stenotic, approximately circular, ring. Diagnosis is made using deep surgical biopsies. Two theories, dysgenetic or acquired, attempt to explain the pathogenesis of this lesion. The predominant acquired theory includes IPHR in the "solitary rectal ulcer" syndrome which is related to the traumatism of rectal prolapse. Transanal ablation is the predominant treatment.