This year, for the tenth time, the European Conference on Object-Oriented Programming (ECOOP) series, in cooperation with Springer, is glad to o?er the object-oriented research community the ECOOP Workshop Reader, a c- pendium of workshop reports pertaining to the ECOOP 2006 conference, held in Nantes during July 3-7, 2006. ECOOP 2006 hosted 19 high-quality research workshops covering a large spectrum of hot research topics. These workshops were chosen through a tight peer review process following a speci?c call for proposals. We are very grateful to the members of the Workshop Selection Committee for their careful reviews and hard work in putting together the excellent workshop program. We also want to thank all submitters, accepted or not, to whom the workshop program equally owes its quality. This selection process was then followed by a selection of workshopparticipants, done by each team of organizersbased on an open call for papers. This participant selection process ensured that we gatheredthe most active researchers in each workshop research area, and therefore had fruitful working meetings. Following the tradition of the ECOOP Workshop Reader, we strove for hi- quality workshop reports that provided added-value compared with a simple summary of presentations held at the workshops. We believe that the result is a thought-provoking snapshot of the current research in object orientation, full of pointers for further exploration of the covered topics. We want to thank our workshop organizers who, despite the additional burden, did a great job in putting together these reports.