The purpose of this paper is to provide an overview of the analysis of data collected by the National Assessment of Educational Progress (NAEP). In simplest terms, the analysis can be characterized as establishing baseline estimates of the percentages of young Americans possessing certain skills, knowledge, understandings, and attitudes and producing estimates of changes in these percentages over time. The baseline estimates permit comparisons of various subgroups. This paper begins with brief descriptions of key activities. The first sections generally describe the methods used to develop objectives and exercises, select the assessment sample, prepare material for the administration of an assessment, administer the booklets, and score the items. The later sections contain discussions about the NAEP analysis including computations used and potential secondary analyses. Appendices cover a variety of topics including adjustment procedures used in the analysis such as balancing and weight smoothing, methods for equating scores across booklets, and an approach for studying response patterns and bias. Primary type of information provided by report: Procedures (Analysis) (Data Processing). (BW)