Quelles sont les contraintes qui pèsent sur les mobilités professionnelles ?

The article analyses how the changes in firm's human resources practices shaped the dynamics of labour market segmentation in France. The survey FQP 2003 contains a rich information to describe jobs. It offers standard information as the sector or the size of the company and also more original information on the concrete conditions of job as the use of the TIC, the rate of work, the contact with the public, the type of hierarchical control... Our approach focused on the permanent contracts. We exploit this information to analyze the link between job characteristics and security of the careers. This work refers to people in salaried employment in 1998, notably on the nature and content of the workstation, enabling to better characterize their trajectories over a five-year period. These movements of mobility could have reflected a transformation of internal labor markets rather than their decline.