238 Copyright © 2013, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 12 INTRODUCTION The number and complexity of service-centric systems for implementing flexible inter- and intra-organizational IT based business processes is steadily increasing. Arising application scenarios have demonstrated the power of service-centric systems that consist of peers providing and re- quiring services (Breu, 2010). These range from the cross-linking of traffic participants, over new business models like Software-as-a-Service, to the exchange of health related data among stakehold- ers in healthcare. Elaborated standards, technolo- gies and frameworks for realizing service-centric systems have been developed, but system testing tools and methodologies have been neglected so far (Canfora & Di Penta, 2008). Michael Felderer University of Innsbruck, Austria Philipp Zech University of Innsbruck, Austria Ruth Breu University of Innsbruck, Austria An Agile and Tool-Supported Methodology for Model- Driven System Testing of Service-Centric Systems ABSTRACT In this chapter, the authors present an agile and model-driven system testing methodology for service- centric systems called Telling TestStories. The methodology has a tool implementation and is based on separated system, requirements, and test models that can be validated in an integrated way. Test models contain test stories describing test behavior and test data in an integrated way. The underlying testing process is iterative, incremental, and supports a test-driven design on the model level. After a general overview of the artifacts and the testing process, the authors employ the methodology and the tool implementation on a case study from the healthcare domain. DOI: 10.4018/978-1-4666-2503-7.ch012