The complexity and the intensity of crisis-related situations require the use of advanced distributed systems infrastructures. In order to develop such infrastructures, specific architectures need to be applied such as Component-based Modelling, Object-Oriented, Aspect-Oriented and Service-Oriented Design. This paper focuses on the use of Service-Oriented Design techniques for the development of the ATHENA Crisis Management Distributed System. The function of the ATHENA Crisis Management Distributed System is based on the use of data generated by social media for the evaluation of the severity of the conditions of a crisis and the coordination of the appropriate measures in response to the crisis. The paper presents a new definition for Service-Oriented Architecture (SOA) and specifies
the benefits that are generated by the use of this new definition in the development of the ATHENA system. Useful conclusions are also drawn in relation to how the definition considers the different technical backgrounds of users
