In Guardians of Medical Knowledge: The Genesis of the Medical Library Association, Jennifer Connor explores the worldview of leaders in American medicine with respect to medical literature, history, libraries, and librarianship. Tracing the first fifty years of the Medical Library Association (MLA) from its conception as a resource for libraries to its post-World War II role as a national, professional organization, this thorough study portrays the "genesis" of the MLA through analysis of its origins, its dominant medical culture, and its intricate network of physician leaders. The MLA began in 1898 in response to an unprecedented expansion of medical literature in the nineteenth century. After North American medical leaders had invented the research medical library and redefined medical librarianship from a custodial to an organizing function, they established the society as a mechanism to improve and update medical libraries primarily through exchange of duplicate materials among member libraries. Beginning with internationally renowned Dr. William Osler, however, successive medical presidents in this circle turned the society into a national forum for historical and cultural pursuits in medicine as well. Connor demonstrates how librarians of the time, mostly women, adopted this dual focus in their occupation and how they dedicated their working lives to serving their physician employers while nudging the MLA toward professionalization of medical librarianship. Guardians of Medical Knowledge delves into the personalities that drove the MLA through its formative period in the first half of the twentieth century to understand how they viewed the society's role not only in medical research, practice, and education, but also in elevating the status of the medical profession. Connor shows how their ideas fit into trends in the professionalization of medicine, the development of academic and public libraries, and the emergence of a separate field of scholarship, the history of medicine.