[영문]This article uses four data sets to assess changes in the relative weights of test- and performance-based merit criteria on college enrollment during the 1980s and 1990s and considers their significance for affirmative action. Our results support the qqqquot;shifting meritocracyqqqquot; hypothesis, revealed by selective postsecondary institutions' increased reliance on test scores to screen students. This shift has made it difficult for institutions to achieve diversity without giving minorities a qqqquot;boostqqqquot; through race-sensitive preferences. Statistical simulations that equalize, hold constant, or exclude test scores or class rank from the admission decision illustrate that reliance on performance-based criteria is highly compatible with achieving institutional diversity and does not lower graduation rates. Evidence from a natural experiment in Texas after the implementation of the qqqquot;top 10 percentqqqquot; law supports this conclusion. The apparent tension between merit and diversity exists only when merit is narrowly defined by test scores.