Book excerpt: This is an edited volume that develops a common understanding of the various technologies intended to facilitate the automation of mediation, choreography and discovery for Web Services using semantic annotations. The volume explores trade-offs among existing approaches, and reveals strengths and weaknesses of proposed approaches, as well as which aspects of the problem are not yet covered. The book is designed for a professional audience composed of practitioners and researchers in industry. Professionals can use it to evaluate SWS technology for their potential practical use. The book is also suitable for advanced-level students in computer science.