In French secondary schools, Senior Educational Advisors (Conseillers Principaux d’Education) are non-teaching staff (Bois et Jacquot 2022) responsible for “school life”, which consists in “placing adolescents in the best pos- sible conditions for individual and collective life, academic success and personal fulfilment” (Circulaire n° 2015- 139 du 10-8-2015). Defining their professional identity is no easy task. Indeed, the official definition of the profes- sion remains somewhat fuzzy as it includes a large range of tasks, from ensuring safety in schools to supporting pupils in their academic and career choices. In schools, the profession is strongly affected by contemporary ne- oliberal reforms given that its members are in charge of implementing education policies. They have no hierarchi- cal responsibilities and nevertheless have managerial functions, as they are responsible for organising and leading the work of the team supervising the pupils. Finally, Senior Educational Advisors’ professional training has been upgraded to master level, as part of the European Higher Education Area. In this paper, we study, in a sociological perspective, the profession’s definition in the light of the knowledge ex- pected on the part of candidates wanting to enter it. The purpose, therefore, is to observe the way in which knowl- edge shapes the profession’s jurisdiction (Abbott 1988). In order to objectify this knowledge, we have chosen to analyse the recruitment process that takes the form of a national competitive exam. We consider the exam both as a ‘barrier’ to entry into the profession and as a ‘level’ within the professional group (Goblot 2010), insofar as it states a series of skills required to become a Senior Educational Advisor, that distinguish them from other professions. In addition to the explicit or formalised knowledge, we seek to reveal the implicit aspects of the exam: these make it possible to highlight the professional ethos or the relationship to knowledge that is sought in the candidates. This paper draws on a wide range of qualitative empirical data. Firstly, we analysed all the texts governing the pro- fession of Senior Educational Advisor and its competitive recruitment exam. We then observed oral recruitments tests between 2014 and 2018. Finally, we interviewed 10 members of the examination board. We will show that the knowledge expected from candidates during the recruitment process reveals the imprecision of the institutional and social definition of the professional jurisdiction of Senior Educational Advisors. After pre- senting the different types knowledge involved and their lack of clarity, we will then show the extent to which they nevertheless refer to a specialised knowledge (Hughes 1971) which defines the specific nature of this profession. Finally, we will show that the study of knowledge points to an autonomation and specialisation process of the pro- fession and that Senior Educational Advisors occupy an intermediate position in the school professional hierarchy.