OBJECTIVE:: This study explores how surgeons define innovation, critically examines and evaluates these views, and uses the findings to develop practical criteria for identifying surgical innovation for ethical and regulatory purposes. BACKGROUND:: Surgical innovation is crucial for progress in surgery, but can be harmful to patients and difficult to identify and therefore support appropriately. Current attempts to define surgical innovation lack precision, and do not give enough guidance to identify innovations in practice. This study is the first to give an account of surgeons' own views about defining innovation. METHODS:: This qualitative study involved interviews with 18 Australian surgeons. Participants provided examples of innovation and distinguished innovation from variations in practice and from research. Data were collected using audio-recorded semistructured interviews. The data were coded using a template and analyzed to develop a thematic account of innovative surgery in practice. RESULTS:: There was no uniform view about innovation, but participants identified 5 features of surgical innovation that distinguish it from variations: newness or novelty; degree of change; level of risk; impact; and requiring formal processes. There was no agreement on the distinction between innovation and research. CONCLUSIONS:: Drawing on surgeons' own views is important for the development of a practical definition of surgical innovation. We have used a critical analysis of surgeons' own views as the basis for defining the core features of innovation. A precise definition of innovation will assist surgeons to identify and manage innovation and thereby enhance patient safety.