This manual has been produced to familiarize data users with the procedures followed for data collection and processing of the second follow-up school component of the National Education Longitudinal Study of 1988 (NELS:88) and to provide the necessary documentation for use of the data file. Chapter 1 contains an overview and the history of the NELS:88 and the studies it comprises. Chapter 2 is a general description of the data collection instruments used in the NELS:88 second follow-up. Sample design and weighting procedures are documented in Chapter 3, including standard errors, design effects, and nonsampling measurement errors. Data collection procedures, schedules, and results are presented in Chapter 4. Chapter 5 describes data control and preparation, and Chapter 6 describes data processing. Chapter 7 describes the organization and contents of the data file and provides suggestions for using it. Fourteen appendixes provide details about the study, the survey questionnaires, guidelines, and a glossary. Twelve figures and 17 tables present information about the survey and its components. (SLD)