The management of lower gastrointestinal bleeding has evolved from a number of technological advances allowing precise diagnosis and localization of the bleeding site. This study of 40 angiographically demonstrated lower gastrointestinal bleeding lesions reinforces much of the data indicating the diagnostic and therapeutic trends. Twenty-four patients had bleeding diverticula with angiographic demonstration in 11 patients. Seven cases of vascular ectasia were identified, and nine patients had a variety of significant bleeding sites other than the two main sites that were listed. Pitressin was useful for control of bleeding in six of seven diverticular patients but was less useful in the vascular ectasia group in which only one patient was actively bleeding. Total abdominal colectomy and segmental resection were successful in control of hematochezia in 24 of 25 operative cases. Sixteen patients did not require surgical treatment.