Context Trend data about critical transitions experienced by students as they leave middle or junior high school, and progress through high school and into postsecondary institutions or the work force. Content The base year of the National Education Longitudinal Study of 1988 (NELS:88) represents the first stage of this major longitudinal effort designed to provide trend data about critical transitions experienced by students as they leave middle or junior high school, and progress through high school and into postsecondary institutions or the work force. The first follow-up in 1990 constitutes the first opportunity for longitudinal measurements from the 1988 baseline. It also provides a comparison point to high school sophomores-ten years before, as studied in HS&B. The dataset captures the population of early dropouts (those who leave school prior to the end of tenth grade), while monitoring the transition of the student population into secondary schooling. The second follow-up took place early in 1992, when most sample members were in the second term of their senior year. The second follow-up provides a culminating measurement of learning in the course of secondary school, and also collects information that will facilitate investigation of the transition into the labor force and postsecondary education after high school. Because the NELS:88 sample was freshened to represent the high school class of 1992, trend comparisons can be made to the high school classes of 1972 and 1980 that were studied in NLS-72 and HS&B. The NELS:88 second follow-up returned to students who were identified as dropouts in 1990, and identified and surveyed additional students who had left school since the prior wave. The third follow-up took place in 1994, when most sample members had completed high school. The primary goals of the 1994 round were: 1) to provide data for trend comparisons with NLS-72 and HS&B; 2) to address issues of employment and postsecondary access and choice; and 3) to ascertain how many dropouts have returned to school and by what route. Data from the fourth follow-up interview in 2000 will permit researchers to examine what this cohort had accomplished 12 years after the eighth-grade baseline survey. The 2000 data were collected at a key stage of life transitions for the eighth-grade class of 1988-most had been out of high school for nearly 8 years. Many had already completed postsecondary education, started or even changed careers, and started to form families. The public use fourth follow-up data is now available. Acknowledgements Data from the National Center for Education Statistics Inspiration What predictors indicate student high school graduation? Or completion of a post-secondary degree? Which descriptors correlate with failing to complete high school?