State testing programs often attempt to provide annual information for use in student guidance and qualification, school and program evaluation, and broad policy decisions. With the development of a new type of assessment instrument, the "duplex design," the several functions of state testing programs can be served in a single test administration requiring no more time and resources than conventional student achievement testing. Using a multiple-form instrument similar to that used in sampling assessment, the duplex design yields profiles of individual student achievement in main content areas, while producing from the same item responses a detailed evaluation of curricular objectives at school, district, county, and state levels. When used in a state-wide census of student attainment, the duplex design serves in one comprehensive assessment the needs of diverse parties to public education for information on student achievement, school performance, and system-wide progress in attaining educational goals. An example of a duplex design for eighth-grade mathematics illustrates the construction of the assessment instrument. Various applications show the potential of this type of testing program. A technical appendix outlines the statistical model by which attainment scores for individual students are estimated on the same scale as those measuring detailed curricular objectives at the school level. Two tables and an 18-item list of references are included. (Author/SLD)