By the late nineteenth century, advances in medical knowledge, technology and pharmaceuticals led to the development of a thriving commercial industry. The medical trade catalogue became one of the most important means of promoting the latest tools and techniques to practitioners. Drawing on over 400 catalogues produced between 1870 and 1914, Jones presents a study of the changing nature of medical professionalism. She examines the use of the catalogue in connecting the previously separate worlds of medicine and commerce and discusses its importance to the study of print history more widely.