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.