Presented at the International Congress on Schizophrenia Research, Santa Fe, N. Mex., April 21–25, 1999. Received Aug. 24, 2000; revisions received Jan. 10 and April 23, 2001; accepted May 3, 2001. From the Department of Psychiatry, Yale University, New Haven, Conn.; Roskilde Psychiatric Hospital, Roskilde, Denmark; Rogaland Psychiatric Hospital, Ullevaal Hospital, and the Departments of Psychiatry and Behavioral Sciences, University of Oslo. Address reprint requests to Dr. Larsen, Rogaland Psychiatric Hospital, University of Oslo, Norway, P.O. Box 1163 Hillevåg, 4095 Stavanger, Norway; tklarsen@online.no (e-mail). Supported by the Norwegian National Research Council, the Norwegian Department of Health and Social Affairs, and the Oslo County Department of Health and Social Affairs (Drs. Vaglum, Johannessen, Larsen, Horneland, Friis, Melle, Opjordsmoen, Guldberg, and Moe). Also funded by the Stanley Foundation, the Regional Research Foundation for Roskilde County, Denmark, Lundbeck, Lilly, and Janssen Pharmaceuticals, and Roskilde County Psychiatric Hospital, Roskilde, Denmark (Drs. Simonsen and Haahr). Also supported by a National Alliance for Research on Schizophrenia and Depression Distinguished Investigator Award and NIMH grant MH-01654 (Dr. McGlashan) and a National Alliance for Research on Schizophrenia and Depression Young Investigator Award (Dr. Larsen).