This essay concerns privacy as a moral right, and as a candidate for protection as a positive legal or constitutional right. It discusses the threefold distinction between what have been termed physical, informational, and decisional privacy rights, and then briefly surveys the efforts to provide a unified theory of privacy in its varying manifestations. The central section of the essay explores the relation between decisional privacy rights and the right to liberty - a relation whose importance is emphasized in the recent decision of the U.S. Supreme Court in Lawrence v. Texas, 123 S.Ct. 2472 (2003). Unlike liberty in the sense of a moral permission to engage in conduct of a given type, decisional privacy is best understood as a right to do wrong - or, more precisely, to do what society, or the legislature, may correctly or incorrectly perceive to be wrong. As such, decisional privacy raises vexing questions about the place of rights in moral and political theory. The essay concludes by suggesting that constitutional privacy might better be conceived in terms of informational privacy rights grounded on individual dignity than in terms of liberty as a decisional privacy right.