Revue française de pédagogie - Année 2002 - Volume 138 - Numéro 1 - Pages 19-28The on the job training seems for everyone, a natural part of the working activity. People would be able to change their point of view to perform the product target and in the same time the goals of training. This article shows that workers have to play with the time constraints to create by themselves a learning situation. We call tempo this capacity to catch in the course of the job, an opportunity to learn. From examples taken in the field of the training within industry, we suggest that this tempo depends on personal involvement in the changing of the activity. 10 pages Source : Persée ; Ministère de la jeunesse, de l’éducation nationale et de la recherche, Direction de l’enseignement supérieur, Sous-direction des bibliothèques et de la documentation.