The availability of adequate and sustainable information systems has become one of the most important success factors for operations in safety critical environments, where life and safety of people is at stake. In this paper the development and the implementation of an information system for public safety is presented. In a more than two-year project various information services for the Austrian Federal Ministry of Interior where conceptualized, tested, and fully integrated in their IT-system environment. The presented case study shows an IT-service development procedure following a dedicated design pattern for systems architecture, design principles aiming for a sustainable service design, and project results in the form of operationally used information services supporting an organization operating in a safety critical environment.