This book contains the papers from invited lecturers as well as selected contributions presented at the 6th International Meeting on Clinical Pharmacology in Psychiatry (I.M.C.P.P.) held in Geneva, Switzerland, 5-7 June 1991. At this meeting the basic theme of the previous meetings in this series (Chicago 1979, Troms0 1980, Odense 1982, Bethesda 1985, Troms0 1988) was continued, namely, to bridge the gap between experimental development and clinical reality in psychopharmacology. After more than 25 years of intensive research in biological psychiatry, basic understanding of the biological mechanisms underlying major psychiatric diseases has advanced significantly but is still far from complete. Likewise, the hypotheses underlying the development of new psychotropics have been refined and produced a wide spectrum of novel, yet designed compounds. The crucial condition for all progress in this field is reliable, informative clinical testing of new compounds. It is our hope that this book, as a continuation of the earlier publications in this series, provides further evidence of the ongoing interaction between preclinical and clinical scientists, who only together can assure progress in this exciting area of research and clinical practice.

The Fourth International Meeting on Clinical Pharmacology in Psychiatry was held in Bethesda, Maryland on 5-8 September 1985 and was dedicated to the memory of Dr. Earl Usdin. Earl was one of the organizers of the three previous meetings held in Chicago (1979), Troms0 (1980), and Odense (1982). During the organization of the fourth meeting Earl became ill and had to relinquish his role as one of the principal organizers. It is safe to conclude that there was no better, or more professional, or more efficient an organizer of scientific meetings in the field of neuropharmacology and psychiatry than Earl U sdin, and it was quite a task for the remaining organizers to fill the void left when he withdrew from this one. Those of us who have organized previous meetings with Earl were struck by how much more difficult our work became without him. This obviously speaks well for his subtle (and at times not so subtle) organizational skills. Nevertheless, in Earl's memory the organizers proceeded to invite a group of internationally renowned neuropsychopharmacologists to address the problem of selectivity in psychotropic drug action and to try to reconcile the amazing advances in basic preclinical neuropsychopharmacology with the problem of clinical specificity encountered by the psychiatrist.

This volume collects the invited lectures and some selected contributions presented at the 5th International Meeting on Clinical Pharmacology in Psychiatry, which was held 26-30 June 1988 at the University of Troms0, Norway. The 24 h of daylight at the northernmost university in the world al lowed for long, pleasant and productive sessions. The title of the conference as well as a number of the topics covered represent a continuation of four previous conferences, the first held in Chicago in 1979 and organized by the late Earl U sdin and colleagues. The earlier conferences have been documented in Clinical Pharmacology in Psychiatry, edited by E. Usdin (Elsevier, New York, 1981), Clinical Pharmacology in Psychiatry. Neuroleptic and Antidepressant Research, edited by E. Usdin, S. G. Dahl, L. F. Gram and o. Lingjrerde (Macmillan Publishers Ltd., London, 1981), Clinical Pharmacology in Psychiatry. Bridging the Experimental-Therapeutic Gap, edited by LF. Gram, E. Usdin, S.G. Dahl, P. Kragh-Sorensen, P. L. Morselli and F. Sjoqvist (Macmillan Publishers Ltd., London, 1983), and Clinical Pharmacology in Psychiatry. Selectivity in Psychotropic Drug Action - Promises or Problems? edited by S. G. Dahl, L.F. Gram, S.M. Paul and W.Z. Potter (Psychopharmacology Series 3, Springer, Heidelberg, 1987)."