This manual has been produced to familiarize data users with the procedures used for data collection and processing of the base year parent component of the National Education Longitudinal Study of 1988 (NELS:88) and to provide necessary documentation for using the data files. Chapter 7 and Appendix F, in particular, contain essential information that allows the user to proceed with minimal startup cost. The rest of the manual provides a wide range of information on a variety of topics, beginning with an overview and history of the NELS:88 and the studies it comprises. Chapter 2 contains a general description of data collection instruments, while chapter 3 discusses the sample design and weighting procedures. Data collection procedures, schedules, and results are presented in chapter 4. Chapter 5 describes data control and data preparation. Chapter 6 deals with data processing, and chapter 7 describes organization and contents of the data files and presents a guide to the codebook. Appendixes contain: (1) the parent questionnaire; (2) a list of critical items from the parent questionnaire; (3) the record layout; (4) specifications for the composite variables; (5) a description of related data files; (6) guidelines for SAS users; and (7) a codebook for the questionnaire. Eleven tables and nine figures accompany the discussion. (SLD)