If you ask any fair-minded person about the greatest injustices perpetrated in and by the United States, slavery would surely be at or near the top of the list. Many arguments have been given in support of the claim that there should be reparations for slavery, and some of them are better than others. Here, I will give one sound argument—The Compensation Argument—for the claim that the U.S. government is morally obligated to pay reparations for slavery. This argument is based upon facts that are not in dispute and on assumptions that all reasonable people share. That is, the argument depends on principles and data accepted by liberals and conservatives, by advocates of and opponents to reparations, and as such it should be acceptable to all who give it a fair hearing.