An arterial sheath with a proximal hemostasis valve and a side‐arm extension tube was used in 562 consecutive patients undergoing cardiac catheterization and angiography via the femoral approach. Serious complications were rare. There was one death, one peripheral embolism, and one episode of delayed groin hemorrhage. The incidence of minor complications, including hematoma formation, in this series compares favorably with our own and the reported experience of others using the conventional percutaneous femoral approach. The sheath technique facilitated catheter exchanges and reduced patient discomfort. In addition, femoral artery pressure could be monitored via the side arm of the sheath during the catheterization. This proved helpful during retrograde catheterization of patients with aortic stenosis, as well as in detection of damping of coronary artery catheter tip pressure during coronary arteriography and hypotension following left ventriculography. Based upon this experience, use of an arterial sheath has become our standard practice when left heart catheterization is performed via the femoral approach, and the use of several different catheters is anticipated. Copyright © 1979 John Wiley & Sons, Ltd.