Social Security’s assets are held in two trust funds invested in U.S. Treasury securities, which help reduce publicly held federal debt. As the funds are drawn down, publicly held debt will need to rise correspondingly. Some question whether keeping Social Security’s assets in trust funds serves a valuable purpose. The answer depends on the context: whether it refers to (1) the Social Security system itself, (2) the federal government, or (3) the national economy. A new issue brief, Significance of the Social Security Trust Fund, explores these perspectives.