We show in this article that while the customer is in principle of the company’s strategies, the professionalisation of customers is organised by the company so that they measure the actions it takes. The professionalisation of customers set up in a catering company, Restocol, is based on rationalisation of customer relations and innovations in the services offered to them. It is mainly carried out by managers by way of argument, which leads to the assumption that there is a technique of relational professions.