As computer systems are being applied to more aspects of personal and professional life, the quantity and complexity of software systems are increasing considerably. At the same time, the diversity in hardware architectures remains large and is likely to grow with the deployment of embedded systems, personal digital assistants (PDAs), and portable computing devices. All these architectures will coexist with personal computers, workstations, computing servers, and supercomputers. Currently, a major goal of academic and industrial computer scientists is to develop techniques to support seamless integration of computer systems in highly heterogeneous environments. The construction of these new software systems and applications in an easy and reliable way can be achieved only through the extensive revise of software components and services.