A Normative Multiagent Approach to Requirements Engineering Serena Villata Department of Computer Science, University of Turin, Italy Abstract. In this paper we present a new model for the requirements analysis of a system. This is a new model based on the multiagent systems paradigm with the aim to support the requirements analysis phase of systems design. This model offers a structured approach to requirements analysis, based on conceptual mod- els defined following a visual modeling language, called dependence networks. The main elements of this visual language are the agents with their goals, ca- pabilities and facts, similarly to the TROPOS methodology [11]. The normative component is present both in the ontology and in the conceptual metamodel, as- sociating agents to roles they play inside the system and a set of goals, capabilities and facts proper of these roles. This improvement allows to define different types of dependence networks, called dynamic dependence networks and conditional dependence networks, representing the different phases of the requirements anal- ysis of the system. This paper presents a requirements analysis model based on normative concepts such as obligation and institution. Our model is a model of semiformal specification featured by an ontology, a meta-model, a graphical no- tation and a set of constraints. Our model, moreover, allows the definition of the notion of coalition for the different kinds of network. 1 Introduction The diffusion of software applications in the fields of e-Science and e-Research un- derlines the necessity to develop open architectures, able to evolve and include new software components. In the late years, the process of design of these software systems became more complex. The definition of appropriate mechanisms of communication and coordination between software components and human users motivates the devel- opment of methods with the aim to support the designer for the whole development process of the software, from the requirements analysis to the implementation. The answer to this problem comes from software engineering that provides nu- merous methods and methodologies allowing to treat more complex software systems. One of these methodologies is the TROPOS methodology [11], developed for agent- oriented design of software systems. The intuition of the TROPOS methodology [11] is to couple, together with the instruments offered by software engineering, the multiagent paradigm. In this paradigm, the entities composing the system are agents, autonomous by definition, characterized by their own sets of goals, capabilities and beliefs. The multiagent paradigm allows the cooperation among the agents with the aim to obtain common and personal goals. In this way, multiagent systems offer a solution for open, distributed and complex systems and the approach combining software engineering and