"The relationship between knowledge and power represents a widely discussed issue in several social sciences and humanities. The TECHDEM research project at the CSIC (Consejo Superior de Investigaciones Científicas, Madrid, Spain) explores the origins of technocracy, examining the ways in which special or expert knowledge has become a source of legitimacy in public debate and in political decision-making. It is an interdisciplinary research that combines approaches stemming from history, history of science and technology, philosophy and sociology of professions. Using the case of experts (mainly engineers and physicians) who have carried out their activity in the northern Mediterranean in the period from the eighteenth century until nowadays, the project pays attention to issues such as the emergence and transformations of the definition of expert knowledge and the ways in which expertise has been acquired and certified. The project also explores how expert arguments and controversies have been inscribed in public debate as well as the ways in which the notion of objective and useful knowledge interacts with key notions of a given period such as “common good”, “public will” or “legitimate search for private interest”. The project does not remain at the level of a discourse analysis, as it also focuses on institutionalisation of expert practices within the government, in the private sector and in the so-called civil society, including the study of the experts’ capacity to mobilise financial resources. In general, the aim is to trace the roots of the raison technique and explore its different forms and transformations in order to set a basis for a well-informed public debate about the relationship between technocracy and democracy, between expert and public opinion, in the society today."