The aim of this paper is to model a liberal profession, in this case physicians. We propose a model in which the physician acts in the same way as an agent who maximises his utility function subject to his budget constraint, while at the same time being able to affect his rate of remuneration. This model presupposes that physicians attempt to reach two target, namely income and leisure, and that the trade-o between these two target depends on their monopolistic power. Unlike existing models, our proposed model advances that some physicians may have a disutility for leisure and may adopt altruistic or strategic behaviours. To determine the relevance of our model, we estimate salaried, firm and agent versions of the model based on a sample of 317 physicians practicing in the Provence-Alpes-Côte d'Azur region (PACA). We observe that physicians do not act like a purely profit-maximising firm. Furthermore, they are able to affect their net remuneration rate through their labour supply. The model that we propose therefore is of particular importance. We estimate that around 20% of physicians experience disutility from leisure, which can be explained by their adoption of altruistic and strategic behaviours. [Authors]