The authors present two cases of therapeutic embolization, utilizing two different foreign materials. In a case of massive gastrointestinal bleeding from a gastric ulcer which had eroded the splenic artery, Gelfoam (gelatin) plugs injected through a gray Kifa catheter resulted in immediate cessation of bleeding. In the other case, rupture of the suture line impended after iliac artery ligation in an infected artery. Injection of Ivalon (polyvinyl alcohol) resulted in thrombosis of the stump, preventing fatal hemorrhage. The procedure may be life-saving in patients who are poor surgical risks.