In the last ten years there has grown up, in the United States, the most extensive organ procurement system in the world. This system, consisting of approximately 120 organ procurement agencies, retrieved 4435 cadaveric kidneys for transplant purposes in 1981. The nation's organ procurement agencies vary greatly in terms of size, organizational structure, and effectiveness. On average, those agencies not formally part of a transplant hospital appear to be the more effective. This can be accounted for by their superior operational flexibility and their pursuit of a “marketing” strategy. Success in organ procurement requires that medical professionals in non-transplant hospitals, and the potential donors' families, be motivated to assist in the organ procurement process.