Personal retirement accounts are attractive in the context of Social Security reform for several reasons. One is that such accounts would give workers ownership and a degree of responsibility over their own retirement saving. Another is that personal accounts would afford participants an opportunity to pass wealth to survivors in the event of premature death. Personal retirement accounts would also benefit divorced persons who receive Social Security spousal benefits unless they remain married ten years. Still another factor favoring personal accounts is that workers could chose how to allocate their retirement saving and diversify their investments over a range of capital market assets. Some also argue that personal accounts would provide all workers a higher rate of return than can be paid under the current Social Security system. In this note, I explore the limits of this last argument. I show that Social Security returns are projected to be low mainly because today’s workers are committed to paying for the system’s past debt. After clarifying several key terms, I discuss reform scenarios involving these concepts.