Margaret Mary Kimmel was born on May 12, 1938, in Gary, Indiana. In her youth, she and her siblings enjoyed listening to stories that her great aunt and great uncle would tell. Originally, when Kimmel began college, she had intentions of becoming a teacher. However, one summer she worked for a public library's trailer (similar to a bookmobile) and decided that she would become a librarian.

Upon getting both her Bachelor of Arts (BA) and Master of Library Science (MLS) from Dominican University, Kimmel set out to be a librarian at the Enoch Pratt Free Library in Baltimore. After working as a librarian for a time, Kimmel spent time freelance writing and teaching at various universities (including the Catholic University of America, Simmons College, the Texas Women's University, the University of Illinois, the Columbia University Summer Institute, and the College of Librarianship). Eventually, Kimmel came to the University of Pittsburgh to work on her PhD. In 1978, Kimmel became an Assistant Professor at the University of Pittsburgh.

Kimmel was well known for her tireless work and dedication to Pennsylvania, literature, and children. For a time, Kimmel did consulting work on the Public Broadcasting Service (PBS) kids' show "Mister Rogers' Neighborhood" and eventually co-edited (with Mark Collins) a book about the show entitled Mister Rogers' Neighborhood: Children, Television, and Fred Rogers(1996).

She was also responsible for generating the imprint Golden Triangle Books. She had noticed that a lot of stories about Pennsylvania were no longer in print and persuaded the University of Pittsburgh to reprint out-of-print stories about Pennsylvania under a newly created imprint—Golden Triangle Books.

Additionally, Kimmel was active in many Pennsylvania, literature, and children centered groups including: the Carnegie 100 (an advisory group to the Carnegie Institute), the Board of Directors of the Children's Council of Western Pennsylvania, the advisory board of Beginning with Books, the nominating committee for the "Kids Need Heroes" campaign, the board of directors of Canterbury Place (an active residence for elders), the board of directors for the Heartwood Institute, the board of trustees for the Carnegie Library of Pittsburgh (member of the Executive Committee and Chair of Automation Committee), the board of directors for the Electronic Information Network, the United States National Section of the International Board of Books for Young People (as past president), the American Library Association Council (as member, chair of the Committee on Accreditation, chair of the Office of Library Personnel Advisory Committee, and chair of the Committee on Education), the Association of Library Service to Children (as past president, chair of the Committee on Accreditation, chair of the Office of Library Personnel Advisory Committee, and chair of the Committee on Education), and the board of directors of the Association for Library and Information Science Education.

"...[I]t was through her narratives that she was sometimes able to effect change," Anya Sostek wrote in the Pittsburgh Post-Gazette. "She helped create the Center for Women with Disabilities at Magee Women's Hospital, advocating for improved facilities, sharing personal anecdotes [herself diagnosed with polio since age four] about her difficulties getting medical services such as a simple mammogram."

In recognition for Kimmel's work for Pennsylvania, literature, and children, she received many awards including "Real Pittsburgher" (Pittsburgh Magazine, 1992), Honorary Degree of Humane Letters (Seton Hill College, June 1992), University of Pittsburgh Chancellor's Distinguished Service Award (1996), Distinguished Daughter of Pennsylvania, Distinguished Alumna of the Year by Dominican University, and Distinguished Service Award from the Association for Library Services to Children.

Margaret Mary Kimmel was a Professor Emerita in the School of Library and Information Sciences at the University of Pittsburgh. She died of Leukemia on June 10, 2014, in Pittsburgh, Pennsylvania. She was 76. Kimmel is survived by her sister, Cathy Kimmel, of New York City, and brother, Mike Kimmel, of Houston, Texas.