 Despite the fact that the origins of reflective equilibrium (minus the name) lie in mid-twentieth century discussions about the justification of inductive logic, its principal development through the rest of the century lies primarily in ethics and political philosophy. Specifically, the method was given prominence (and the name by which it is known) by John Rawls's description and use of it in A Theory of Justice (Rawls 1971). (Rawls 1951 had much earlier articulated a slightly different version of the view.) Although accounts of the justification of empirical knowledge have been developed that share with reflective equilibrium its coherentist approach, they generally do not make explicit use of the terminology of reflective equilibrium, and we shall not discuss them here. Instead, we concentrate on the use of reflective equilibrium in ethics and political philosophy, where it has been deployed and criticized.