In any company or organisation, optimising processes and making rational use of available resources is crucial. In a manufacturing context, in most companies, production lines are characterised by a high turnover of workers and some degree of manual processing, which makes differences in workers’ skills a major challenge. In this context, the human factor is very relevant, since the competences and capabilities of workers profoundly affect the performance of production systems. This means that, in addition to the problems of line balancing, another aspect that is considered when analysing production systems refers to the problems of assigning people to jobs or work operations. The focus of this work is on the allocation of human resources to jobs and/or operations considering both their restrictions and their work experience, aiming to maximize the overall performance of the system. To solve this problem, two integer linear programming models were developed and implemented, which follow two different approaches: a parallel approach and a sequential approach. Each of these approaches has been tested and validated with a real case.