Our team consisted of sixteen members; two members unfortunately could not attend both meetings; for one participant a replacement could be found. The people involved in this international team were Xavier Barcons (Spain), Johan Bleeker (Netherlands, co-organiser), Andrei Bykov (Russia, co-organiser), Stefano Borgani (Italy), Antonaldo Diaferio (Italy), Klaus Dolag (Germany), Florence Durret (France), Jelle Kaastra (Netherlands, organiser), Jukka Nevalainen (Finland), Takaya Ohashi (Japan), Frits Paerels (USA), Vahé Petrosian (USA), Yoel Rephaeli (Israël), Philipp Richter (Germany), Joop Schaye (Netherlands), Sabine Schindler (Austria, co-organiser), and Norbert Werner (Netherlands). In addition a few people outside the team helped in writing the review papers or even have taken up the lead in writing these papers: Serena Bertone (UK), Chiara Ferrari (Austria), Federica Govoni (Italy), Dunja Fabjan (Italy), Luca Tornatore (Italy), and Rob Wiersma (Netherlands).
Our team started with a one week meeting at the end of October 2006 at ISSI in Bern. Each team member introduced a topic, and in the following discussion the relevant issues for the review were collected. After the discussions, subteams were formed around the different topics, and the outlines of the different chapters as presented in the present volume were defined. Each team member participated in several subteams and papers, either as first author or co-author. In the time between the first and the second meeting, several subteams were able to work out these drafts further. At the second meeting, the progress was reviewed, comments were made on the drafts and the remaining time was used to work further on the drafts.
After the second meeting, the draft papers were finished by the authors and sent to two internal referees from the team who are non-experts in the field, in order to check the comprehensibility of the papers and of course for the normal work of any referee. All papers were then reviewed by an anonymous, external and expert referee. That there was a lively discussion and interaction is proven by the more than 700 emails that were exchanged between the authors and the editor between July and December 2007.