Although considerable attention has been given recently to competing concepts of fair selection, little attention has been focused on the determination of “acceptable” performance, a central concept in several such models. The determination of “acceptable” performance in Thorndike's “constant ratio” standard of fair selection is considered in this paper. First, it is shown that, given the assumptions typically made about the distribution of test scores and performance in minority and majority populations, suitable choice of “acceptable” performance can make any minority-majority selection disparity consistent with Thorndike's standard. Thus, the determination of what constitutes “acceptable” performance is a key element in evaluating Thorndike's standard. Second, a rule for determining acceptable performance is proposed: If X% of all applicants (minority plus majority) can be accepted, then acceptable performance is the level of performance which X% of all applicants could reach if hired. In addition to avoiding the Petersen-Novick paradox, determining acceptable performance in this way has other reasonable intuitive properties which alternative approaches lack.