The purposes of this study were to examine the reliability and validity of a basal reading series mastery test, and to explore the appropriateness and usefulness of two strategies for investigating the reliability and validity of criterion-referenced tests. Subjects were 47 sixth graders, who were tested on the SRA Reading Achievement Test, the Houghton-Mifflin End-of-level 11 Basic Reading Test (BRT), and the Word Reading Test. A subgroup of 20 children was tested a second time on the BRT. Traditional psychometric correlational analyses as well as specific strategies for examining the adequacy of criterion-referenced tests were applied to the data to investigate the following dimensions of the technical adequacy of the BRT: (1) consistency of student performance across two administrations of the BRT, and (2) criterion validity of the BRT scores with respect to two other measures of reading proficiency and criterion validity of the BRT mastery/nonmastery decisions with respect to pre/post instructional status. Results indicated that the reliability and validity of the BRT was less than adequate, and that both strategies for investigating the adequacy of a criterion-referenced test were useful and provided complementary information. Implications for the development and use of criterion-referenced instruments are discussed. (Author)