Currently available reconstructive vascular surgical techniques have made complete and detailed mapping of the major vessels of the lower extremities of fundamental importance. Experience in this field has shown that the velocity of blood flow in extremities is often quite unpredictable. Thus, if one wishes to visualize the arterial tree from the aortic bifurcation to the popliteal trifurcation, along with important collateral vessels in both lower extremities simultaneously and completely, serial exposures of long cassettes are essential. While this principle has been accepted by many observers, and various modifications of the technique have been practiced in many large centers,1-16 it is not yet generally used in the average hospital for femoral arteriography, possibly because of the complexity or expense of most serial long-casette changers. Accordingly, many surgeons have been content with incomplete studies and substandard arteriograms, to avoid multiple injections or repeated examinations in patients in whom the velocity