In this paper, I explore the role of technocracy and the political power of experts by examining how a particular group of experts – namely health economists – started influencing the governance of British health policy from the 1960s. Examples such as the formulation of concepts for valuing life economically (the Quality-Adjusted Life-Years (QALYs)), new formulae for allocating health resources geographically, and introducing new ideas of competition and cost-benefit analysis for the reform of the National Health Service (NHS) illustrate how economists begun formulating problems and solutions in health policy. From the hiring of economists in the Department of Health (DH), to the commissioning of research from academic economists, and the creation of the National Institute for Health and Care Excellence (NICE) in 1999, an independent organisation deciding on the effectiveness of treatments, it is necessary to problematise this emergence and supposed dominance of these experts. In doing so, I seek to understand how this expertise is actually mobilised by policy-makers – i.e. politicians and civil servants (Fischer 1990; Frankford 1994). Here, I build on research from the knowledge transfer (Boswell 2009; Parkhurst 2016; Radaelli 1999) and depoliticisation (Flinders & Wood 2015) literatures, combined with rich qualitative data – notably 42 semi-structured interviews with civil servants and academics – to critically analyse and repoliticise the role of expertise. By examining given practices and techniques, this study seeks to build a more complex picture of the changing and sometimes uneasy relationship between experts and politicians in British health policy-making and its consequences for negotiation and accountability.