The purpose of this study is to provide data for making decisions on whether to buy or borrow research materials and whether to use fee-based suppliers or interlibrary loan for obtaining photocopied materials. The study is based on 1991 information collected in a survey of 76 U.S. and Canadian research libraries. The cost per transaction is broken down into the following categories: staff; networks and communications; materials delivery; photocopying; supplies; equipment and software purchase, rental, and maintenance; and direct and indirect charges for borrowing. The study highlights cost differences among geographic regions and between private and public institutions, which are due to variations in staff deployment and salaries, service levels, and numbers of borrowing and lending transactions. Analysis of the data shows that a research library spends on average $18.62 to borrow a research document or article or to purchase a photocopy of the item and $10.93 to lend a document. Staff costs represent about 77% of the cost for borrowing and lending; 16% of the total is for supervisory staff and 61% for nonsupervisory staff. A copy of the survey instrument is appended. (KRN)