The technique for downstream abdominal catheterization is described. The technique is simple and results in superior angiograms. The introduction and advancement of the catheter in the abdominal aorta, either downstream or upstream, permits the use of a power injector which allows safe delivery of an adequate amount of contrast medium in a short period of time without danger of extravasation. In our experience translumbar aortography, either downstream or upstream, is one of the safest angiographic procedures, being less hazardous than percutaneous catheterization via the femoral artery or the left axillary artery.2 The main reason for improved contrast density is the delivery of contrast medium below the level of the renal arteries, where the aortic flow is markedly reduced, and the propulsion of the contrast medium during diastole towards the peripheral artery. Dye dilution studies performed with catheters directed in the downstream and upstream directions showed a marked difference in concentration. From these studies it is suggested that any type of angiography preferably should be performed in the downstream fashion. This is particularly true in translumbar aortography, femoral arteriography, and brachial angiography.