Explaining what people do oneself and others and what happens to them is an everyday activity in the professional life of numerous decision-makers managers, headhunters, recruiting officers, teachers, work and organizational psychologists, clinical psychologists, educational psychologists, etc. In this article we shall see that such activities, due to their social utility, can be not just the expression of an act specific to an individual or an organization, but the expression of a norm, the norm of internality. We shall look first at a certain number of results which confirm the theory of the norm of internality and its general nature. We shall note that: 1 causal explanations of events are socially acquired and that some explanations internal are deemed more acceptable than others external; 2 that this predilection can lead to a social selection process which favours those giving internal explanations, and that this is especially prevalent in particular situations where people have to give a good impression appraisal, recruitment, etc. We shall consider, alongside these two points, the factors likely to modulate the functioning of this norm: management styles, evaluation practices, hierarchical status, and the sensibilities of employees. After considering a series of research projects designed to study the norm of internality in an organizational context, we shall discuss, on one hand, the link between this norm and the social situation, and on the other hand, its implications for organizational practices. More generally, we shall show how this socio-cognitive inspired approach can give rise to activities of reflection and application in organizations.