Major breakthroughs in catheter, guidewire, and other angio-graphic equipment currently allow interventional radiologists to diagnose severe active upper and lower gastrointestinal hemorrhage and to stop the bleeding safely and effectively using super-selective catheterization and microcoil embolization. Similarly, the interventional radiologist can diagnose and treat acute intestinal ischemia safely and effectively with selective catheterization and papaverine administration and can treat chronic mesenteric ischemia by percutaneous angioplasty and stent placement. This article reviews the role of diagnostic and therapeutic radiologic procedures in acute or chronic gastrointestinal bleeding and intestinal ischemia, with a focus on recent advances.