Résumé
In this paper we describe MASQ (Multi-Agent Systems based on Quadrants), a model that defines four perspectives over an agent-based interaction according to two axes: internal/external and individual/collective. With MASQ, we mainly show how to integrate the essential elements that intervene in the description of the interaction process such as agents, environments, organizations and institutions. We also discuss some methodological aspects of such an approach and show that it is possible to apply it to build practical models.