This thesis studies the change in the Moroccan hospitals and contributes in the field of change management. The result of our research is a new method of change management. This method represents the proposed change through the perceptions of those involved in this change, incorporating it into a strategic planning. This is the Actors Representations of Change method which is based on a teamwork and a modeling of internal and external factors influencing the hospital change. Indeed, the hospital organization has certain characteristics tightly linked with the question of change management....