In the spring of 1980, the High School and Beyond (HSB) base year survey collected data from about 28,000 seniors and about 30,000 sophomores in more than 1,000 secondary schools. This supplement was designed to collect data concerning the methodology associated with the receipt of postsecondary financial aid within the first 4 years after high school for selected members of the HSB senior and sophomore cohorts. Financial aid data were collected for students in the sophomore cohort (n=10,026) during 1986-87 for the 1982-83 through 1985-86 academic years. Senior cohort (n=10,708) data were collected for the 1980-81 through 1983-84 school years. Sources of data include federal records of the Guaranteed Student Loan (GSL) program, federal records of the Pell Grant Program, and yearly GSL disbursement data from guarantee agencies participating in the GSL program. In addition, for students in the senior cohort, financial aid data were collected from the postsecondary institutions that the students reported attending. Original and follow-up data collection techniques, which depended on mail and telephone contacts and extraction of data from data bases, are described; and software and data entry and editing are discussed. Administration of the Institution Financial Aid Records Survey to the senior cohort is discussed; and the methods used to extract data from the records of the state guarantee agency GSL program, the federal guaranteed student loan program, and the Pell Grant disbursement program are described. Problems associated with confidentiality and non-response are also covered. Seven data tables, three figures, and eight exhibits are presented. The bulk of the document consists of 14 appendixes which provide copies of the data collection and processing plan various training and procedural manuals, and other forms and materials related to the research. (TJH)