On April 1, 1992, Otto Creutzfeldt would have celebrated his 65th birthday. About a year before, those of us who worked with him in the Department of Neurobiology decided to organize a meeting to honour Otto and his contri butions to neuroscience. Since Otto Creutzfeldt had no intention of retiring before his 67th birthday, this was not to be a "retirement conference" but a celebration on the occasion of a major anniversary. However. events turned out differently. In the spring of 1991, Otto Creutzfeldt became seriously ill, before we could consult with him on his suggestions for such a meeting, and we decided to postpone further dis cussion until his health improved. In the summer, when we talked to him about the meeting, he basically approved of the idea but immediately sug gested our turning it into a proper scientific congress, rather than limiting ourselves to inviting his friends and former co-workers. He had very good friends in many parts of the world and would certainly have liked to see many of them again. However, his interest in science remained the domi nant factor. He proposed the main topics for the conference and suggested several speakers to be invited. Although he knew that his health was crit ical and that his condition could rapidly worsen, we had the feeling that the planning gave him hope and perhaps an opportunity to look forward."