A recent debate about the Bush administration's use of presidential signing statements has raised questions about their function, legality, and value. We argue that presidential signing statements are legal and that they provide a useful way for the president to disclose his views about the meaning and constitutionality of legislation. Although President Bush has challenged more statutory provisions in signing statements than prior administrations have, his signing statements are similar in many respects to the signing statements issued by prior presidents, such as President Clinton. In addition, basic tenets of positive political theory suggest that signing statements do not undermine the separation of powers or the legislative process and that, under certain circumstances, they can provide relevant evidence of statutory meaning.