The Averly foundry in Saragossa is an enterprise belonging to the mechanical constructions branch. It opened in 1863 with eight workers, and by the end of the XlXth century it employed one hundred workers. This article tries to understand the labour policies developed by this family enterprise, as a function of its market outlook and its type of work organization, based on a division of jobs and tasks by qualifications. Looking at these policies, we consider this firm as an example of what is called «flexible specialization», with productions adapted to demands and customers' needs.