Over the last 15 years, and in a context of globalisation competence management has become an essential lever of competitiveness in companies, and an essential factor in industrial processes' performance. However, competences management requires relevant modelling of competence, given its complex nature and the evolution of the company's activities. In this paper, we propose an activity-based model of competence to represent competences mobilized during an activity. A specification of terminology is first defined around the concept of competence, and then we define its different characteristics. Finally, after a study of the main models proposed in the field of industrial engineering, we present an activity-based model of competence.