The principle of fair equality of opportunity is regularly used to justify social policies, both in the philosophical literature and in public discourse. However, too often commentators fail to make explicit just what they take the principle to say. A principle of fair equality of opportunity does not say anything at all until certain variables are filled in. I want to draw attention to two variables, timing and currency. I argue that once we identify the few plausible ways we have (...) at our disposal for filling in those variables, it will become apparent that a reasonable version of the principle will be quite narrow. Its usefulness as a justificatory basis for social policies will be limited to those policies that target the distribution of competitive opportunities among people entering majority. (shrink)