The management of critical systems exposes human operators to increasingly complex problems and to an ever-growing mass of data. These problems constitute a major challenge for operators, for example in terms of finding relevant information, understanding the situation, identifying the causes of problems, and making decisions, especially in contexts of high time pressure. In this paper, we present the user-centered design approach developed to design an AI-based system whose objective is to assist operators in these contexts. This system is characterized by its genericity; it covers different work situations involving critical systems (airplane, IT system, electrical network, railway transport). It aims at assisting operators in real time in or monitoring and piloting activities