S.A.T. scores are valid, reliable and consistent over time for all groups. Differences in score levels point to the unfinished task of providing quality education for all. For the last 63 years, the S.A.T. has functioned as a guarantor of fairness to students of every background in college admissions. It has been a messenger of clear national standards of academic achievement that help to keep high school grades from ''inflating'' beyond reason. In a time of economic competition, when our future standing among nations depends on a highly educated work force, the S.A.T. is one of the only bulwarks of fair, high quality learning for all.