This collection of papers offers real-life application experiences, research results and methodological proposals of direct interest to systems experts and users in governmental, industrial and academic communities. This book also documents several important developments. The uptake of distributed computational infrastructure oriented to service provision, like Web-Services and Grid, is making C&S even more important. E-services based on legacy systems managed by autonomous and independent organizations, a common situation in the public administration sector, increase overall complexity. The increased presence and use of e-service IT-infrastructures depends on the critical ability required for all security issues, from the basic (availability, authentication, integrity, confidentiality) to the more complex (e.g. authorization, non-repudiation), to track responsibilities, --"who did what".