Grace Hamlyn worked for many years at McGill University in the Redpath Library, the Commerce and Law Library, the Undergraduate Library, and the Medical Library. She then continued her career as a hospital librarian for the Royal Edward Tuberculosis institute which later become Montreal Chest Hospital. From 1956-63, Grace had a UNESCO fellowship for the study of international government documents, which involved travel to the United States and Europe. She was in attendance at the Second International Congress on Medical Librarianship in Washington, D.C. and delivered welcoming remarks in French, one of the three official languages at the meeting.
Grace was born in Toronto and was raised in London. From an early age she wanted to be a librarian and almost abandoned her dream when she developed diabetes as a teenager. Her physician eventually convinced her that a chronic disease did not preclude university attendance. She earned a general bachelor of arts degree at McGill and then continued in the one-year library course. Grace was especially pleased that the year she received her library science degree from McGill was the same year that Frederick Banting was awarded an honorary degree. Everyone in her library school class of thirteen was successful in finding employment which was a marked contrast from the 30s.
Grace was afforded opportunities for career advancement at McGill University, including the senior position in the Medical Library. "I felt I had a contribution to make because I knew so much about libraries. But if I had been a young person, I'd have wanted to have an awful lot more of medicine, for my own confidence in being able to do the position." Given the library's long tradition and excellent collection, Grace made her mark focusing on service. She also had the burden of planning a new library in a round building. For this project, she relied heavily on consultants. "I would speak very much for the value of consultants in any building and especially with libraries, and with the distinctive things that you want to have for libraries. Also, because medical people, you know are pretty sure they know what's best for everybody. It's quite good then, to have authoritative people supporting you. So they listened very respectfully to these ideas that we came forth with, from having talked to the experts in our field."
Grace joined the Medical Library Association in 1956 when she assumed the administrative position at the McGill Medical Library. She was on the Publications Committee and attended several regional and annual meetings. At these meetings, the Canadian librarians met together over breakfast. At the Toronto meeting in 1959, discussion among those in the group of medical school librarians was on how to improve access to resources on a national level. She returned to McGill and consulted with the Dr. Stevenson, the Dean of Medicine. "So we thought it would be quite nice if the McGill collection became the National Library of Canada, working with all the other medical faculties. The National Library of Canada would be contained in the Medical Faculty libraries of the country. We thought this was an interesting different approach than the United States had..." Grace recalled that the Association of Canadian Medical Colleges was in its beginning stages at this time. Its Executive Director, Dr. MacLeod, convened a meeting of the deans and librarians which lasted for a day and half. The outcome of this 1962 meeting was the agreement to do a survey about libraries with funds donated by each of the deans. Beatrice Simon, who was then Assistant Librarian at McGill, took on the project. "She traveled from coast to coast and interviewed the deans and the librarians, and the Simon Report was published in about 1965..." This informal group of librarians then went on to form an affiliation with the Canadian Library Association to continue the work on medical library development.