Preface VII was composed of six overview talks centered around the state of the art, serving to inform the heterogeneous audience, and 13 technical presentations of mainly young researchers working in related areas.Presentations, an abstract collection of all contributions, and an executive seminar summary can be found at the Dagstuhl Web site [3]. Twelve of the seminar contributions have been elaborated as full articles for this post-proceedings volume. Additionally, a highly relevant paper from Alex Stoytchev has been invited to complement the seminar contributions.The organizers express their gratitude to the Dagstuhl foundation for their support and for hosting this seminar in their exceptional facilities, and to the participants for their contributions and for making the seminar successful and enjoyable.