This guide for administrators of student financial aid programs at postsecondary education institutions is intended to assist in interpreting the codes that appear in the Student Aid Report (SAR), which is sent directly to the student, and in the Institutional Student Information Record (ISIR), which is an electronic report sent directly to institutions by the U.S. Department of Education. An introductory chapter identifies major system changes for 1998-99, such as changes to the Student Aid Report, changes in the processing flow, and highlights and assumptions of the electronic system. The second chapter explains in detail the information summaries on the SARs and ISIRs, such as record types, verification types and flags, Pell digits, the dependency override function, reprocessing codes, reject reasons, and subsequent application flags. The third chapter explains how to perform corrections and updates on the Information Review and the Information Request forms, and explains the parent information for independent students section. Seven appendices include information on reject codes and reasons, data base matches and match flags, 1998-99 comment codes and text, list addresses, and shows sample SARs, SAR information acknowledgments, and sample ISIRs. (DB)