Social computing seems to be the new trend in Web applications development. FaceBook, Twitter, and LinkedIn are examples of a growing number of social applications that have reinforced the role of the Web as an inevitable communication means in this 21st cen- tury. FaceBook, alone, counts more than 350 million members in 2009, and more than 100,00 blogs are created daily. Social networking introduces a new dimension to the Web that goes beyond the exercise of connecting HTML pages; it opens up new forms of communication channels between people and between communities. Socializing over the Web lets people engage in various activities like looking for old friends, posting job announcements, and establishing new contacts. Parallel to the growing interest in integrating social elements into Web applications de- velopment, service computing rises as another alternative to this development. In response to challenges that modern enterprises face such as agility and competitiveness, today’s ap- plications need to be loosely coupled and capable to cross organization boundaries. Web services are a core technology that showcases the value-added of service computing to enterprises. A long list of standards and specifications (WS-*) sustain the adoption of Web services, besides the possibility of composing separate Web services to generate new added-value services. Someone would wonder the synergy that might exist between social computing and service computing. On the one hand, social computing allows to reflect relationships that people daily experience like friendship and dislike on automated structures known as social networks. On the other hand, service computing allows to develop applications as per the basic principle of “I offer services that somebody else may need” and “I require services that somebody else may offer”. Offering and requiring services raises issues such as how to advertise services to the external community, how to discover services with respect to needs, how to trust services when they are found, and how to replace services when they 1www.FaceBook.com, visited in Fall 2009. We address some of these issues by capturing the way the Web services interact with peers using social networks. Indeed services evolve in a dynamic environment in which they compete against peers so they can be selected, collaborate with peers so they can altogether work on complex users’ requests, substitute peers in case of failure so a high- level of availability can be achieved, just to cite a few examples of all the interactions that services initiate and hence, can be used for building these services’ social networks. Our work on social networks and Web services has two main goals: build Web ser- vices’ social networks and support Web services use these networks. We motivate our work further in the next section. After that a running example illustrates the nature of interactions between Web services. Details on what we refer to as social Web services are given prior to showing some experiments, discussing some related work, and drawing some conclusions.