ABSTRACTA national sample of Scholastic Aptitude Test (SAT) candidates was surveyed to determine the ways in which they had prepared for the examination. Candidates' SAT scores were retrieved from test files, along with selected background information that included rank in high school class and scores on the Preliminary Scholastic Aptitude Test (PSAT), which most students had taken about eight months before they took the SAT.Multiple regression analyses revealed effects of less than ten points on the 200‐800 SAT score scale and less than two points on the 20–60 score scale for the Test of Standard Written English (TSWE) for each of the methods of test preparation. A significant number of negative effect estimates, coupled with significant differences between the background characteristics of preparing and nonpreparing groups, strongly suggested the influence of selection bias in the estimates. Exploratory analyses of the effects of combinations of methods of preparation showed that various methods may interact in complex ways with other methods and with some student traits. Furthermore, self‐selection may not be uniform across levels of ability and previous achievement, and may also depend on the candidates' selection of other methods of preparation. The implications of the results for the design of further research on the effects of special preparation for tests are discussed.