This volume includes the proceedings of all the ?ve workshops that were held as part of the International Conference on Service-Oriented Systems 2007 (ICSOC 2007): – Mashups 2007: First International Workshop on Web APIs and Services Mashups – NFPSLA-SOC 2007: Workshop on Non-Functional Properties and Service Level Agreements in Service-Oriented Computing – SeMSoc 2007: Second International SeMSoC Workshop Business-Oriented Aspects Concerning Semantics and Methodologies in Service-Oriented Computing – TSOA 2007: First International Workshop on Telecom Service-Oriented Architectures – WESOA2007:ThirdInternationalWorkshoponEngineeringService-Oriented Applications: Analysis, Design and Composition These workshops o?ered interesting presentations and discussions on a wide rangeofhottopicsinservice-orientedcomputing:developmentofmashups,m- agement of non-functional properties and service level agreements, engineering approaches, and semantic methodologies. Also, the crucial application domain of telecom services and service architectures was investigated. The ?ve workshops were selected out of eight submissions. During the - lection process we encouraged the merging of workshop proposals with similar scope. We are grateful to all workshop organizers. Without their valuable ideas and support the workshop sessions at ICSOC as well as this volume would not have been possible. We also thank all authors for their active participation in the events, for the quality of their papers, and for being patient with us during the long process of compilation of this volume.