No / The terms ‘extended’ and ‘advanced’ practice are commonly used to describe clinical practitioner roles. However, these terms have not been clearly defined within the context of modern radiography practice despite their fundamental importance to establishing the 4 tier structure, implementing Agenda for Change and promoting a coherent clinical radiography career structure. This paper discusses the terms ‘extension’ and ‘advancement’ in relation to radiography practice and, using evidence from the debates of other health professions, attempts to offer some clarity to the terminology, presenting one interpretation of its possible application to the radiographer role in the United Kingdom.