[영문]Alford's theory of structural interests has been used as a framework within which to analyse health systems across the world. However, authors have often been uncritical in their acceptance of Alford's original analytic categories. In this article we use data from a detailed qualitative study of the introduction of Practice Based Commissioning in the UK NHS to interrogate Alford's work more critically. Disrupting Alford's original categories of ‘professional monopolisers’ as dominant interests, challenged by management ‘corporate rationalisers’, we suggest that the new structures established in the NHS since 2002 systematically privilege an interest that we call ‘corporate monopolisers’, and that this is under challenge from ‘professional rationalisers’.