The position that the National Assessment of Educational Progress (NAEP) provides a data base that is compatible with various definitions of literacy and standards of competencies and can make a contribution to our understanding of the complex and controversial problem of literacy is supported in this paper. The paper notes that since the NAEP has surveyed a national sample of four age groups over a period of years since 1971, it is well suited for looking at a broad sample and providing longitudinal information. Other advantages of the NAEP for studying literacy that are cited are its comprehensiveness across many areas of study and functional skills, its breadth within single content areas, its covering of affective and background variables as well as achievement, and its ability to respond to new emphases, such as the proposed 1979-80 reading and literature assessment that has new exercises emphasizing comprehension of various kinds of texts. The use of the NAEP data base for the assessment of functional literacy conducted by NAEP in 1974 and 1975 for the National Right to Read program is discussed as an example of the use of the NAEP data base. (MKM) Primary type of information provided by report: Procedures (Conceptual).