These simulations suggest 3 important patterns: (a) practical SES-based affirmative action policies do not yield nearly as much racial diversity as do race-based policies; (b) there is little evidence that affirmative action policies produce systemic academic mismatch; on average, affirmative action policies do not sort minority students into colleges for which they are academically unqualified; and (c) the use of affirmative action policies by some colleges affects enrollment patterns in other colleges.