The 16 contributions published in this volume were carefully selected from 45 submitted works in a rigorous peer-reviewed process. In addition to this 3 distinguished researchers were asked to contribute 3 invited papers.

The papers examine research challenges facing system development and software support for wireless sensor networks (WSNs). Currently, wireless sensor networks introduce innovative and interesting application scenarios that may support a large amount of different applications including environmental monitoring, disaster prevention, building automation, object tracking, nuclear reactor control, fire detection, agriculture, healthcare, and traffic monitoring. The widespread acceptance of these new services can be improved by the definition of frameworks and architectures that have the potential to radically simplify software development for wireless sensor network based applications. The aim of these new architectures is to support flexible, scalable programming of applications based on adaptive middleware. As a consequence, WSNs require novel programming paradigms and technologies. Moreover the design of new complex systems, characterized by the interaction of different and heterogeneous resources, will allow the development of innovative applications that meet high performance goals. Hence, WSNs require contributions from many fields such as embedded systems, distributed systems, data management, system security and applications.