This article describes the 2009 revision of the Dutch Rating System for Test Quality and presents the results of test ratings from almost 30 years. The rating system evaluates the quality of a test on seven criteria: theoretical basis, quality of the testing materials, comprehensiveness of the manual, norms, reliability, construct validity, and criterion validity. The update concentrated on two main issues. First, the texts of all criteria were adapted to apply to both paper-and-pencil tests and computer-based tests. Second, the items and the recommendations with respect to the seven criteria were extended to include new developments. The most important extensions are item response theory for test development, continuous norming, domain-referenced interpretation and criterion-referenced interpretation, and the use of non-traditional, modern types of reliability estimation. Longitudinal results show a steady increase of average test quality, but the quality of the norms and the (lack of) research on criterion validity still appear to be a matter of concern. (Contains 2 tables and 4 notes.)