E d i t o r i a lof remarkable authors, whom I would like to thank warmly for their contribution. I wouldalso like to thank Pierre Schulz for being the Coordinating Editor of this issue.This also represents for me an opportunity to point out that Professor ManfredAckenheil shared with me, over many years, ideas and projects on the theme of proof ofconcept. Manfred Ackenheil has just passed away; it is with great sadness that I bring youthis news, both on my own behalf and that of the Editorial Board of Dialogues in ClinicalNeuroscience, of which he was a founding member. He was working as the CoordinatingEditor of issue no 32 of our journal, and this issue, to be published in early 2007, will bean In Memoriam issue dedicated to Manfred Ackenheila tribute to a man of scienceand to a friend.Jean-Paul Macher, MD