Robert Nozick’s Anarchy, State, and Utopia made libertarianism a major theory in political philosophy. However, the book is often misread as making impractical, question-begging arguments on the basis of a libertarian self-ownership principle. This essay explains how academic philosophical libertarianism since Robert Nozick has returned to its humanistic, classical liberal roots. Contemporary libertarians largely work within the PPE (politics, philosophy, and economics) tradition and do what Michael Huemer calls “non-ideal, non-theory.” They more or less embrace rather than reject ideals of social justice, and they accept that positive liberty is important. The difference between them and Left-liberals is not so much a dispute over fundamental values, but empirical disagreements about the extent of market versus government failure.