Transcatheter embolization was performed in 7 patients with lower gastrointestinal bleeding. Hemorrhage was controlled in each of the 5 actively and massively bleeding patients but recurred after several months in 2 patients who had bled intermittently from vascular dysplasias. The authors recommend preoperative angiographic localization of the bleeding site in almost all cases of major lower gastrointestinal bleeding. When the cause and bleeding site have been identified, it seems reasonable to exploit the therapeutic potential of the angiographic catheter already in place: indeed, surgery may be obviated. If embolism fails or ischemic sequelae develop, partial colectomy can still be performed. Further long-term follow-up will be necessary before the role of transcatheter embolization can be definitively assessed.