This paper contains an estimation of transition intensities on the French Labor market between 1981 and 1989. It generalizes the results of Fougere and Kamionka [1992] computed between 1986 and 1988. The estimation of the continuous markov process is made on a four state labor market (inactivity, unemployment, marginal jobs and regular jobs). Young people, women and individuals without formation have a highier labour instability. This instability has increased during the eighties in particular for young people.