The empirical experiments reported in this book show that VPP is an effective platform. During its design, editors faced many challenges, the results and the methods we used to face them are reported in this book.Many people have contributed to the results of the project in many ways and their contribution has been essential in making VisiOn a successful project. The editors would like to thank for the hard work of all the participants of the projects. In particular, the editors would like to thank the EU project officers who supported the project during lifetime, the reviewers who provided valuable feedback at the project reviews.