Margaret A. Leary became director of the Law Library in 1984 and retired in 2011. From 1973 to 1981, she served as assistant director and from 1982 to 1984, as associate director.

Leary worked to build the comprehensive library collection to support current and future research in law and a wide range of disciplines. She also developed strong services to support faculty research. Her biography of William W. Cook was published by the University of Michigan Press in fall 2011. Giving It All Away: The Story of William W. Cook and His Michigan Law Quad describes Cook's family background, his education at Michigan, and his great success in New York City, which generated the money he was to give to Michigan Law.