This book is the result of my research perfonned at the University Kiel under the supervision of Professor Dr. Andreas Drexl. I am very grateful to him for suggesting the subject as well as for his guidance and support during the preparation. Professor Dr. Klaus Brockhoff deserves thanks for under- taking the task of the secondary assessment. The Institut fur Betriebswirtschaftslehre in Kiel and especially my col- leagues Dr. Knut Haase, Carsten Jordan, AlfKimrns, and Dr. Frank Salewski provided a stimulating environment. Particularly, I am indebted to Dr. Arno Sprecher and Andreas Schinner. The results of Chapter 2 and 3, respectively, are outcome of joint research with Arno; Andreas proof-read the entire manuscript. Furthennore, I would like to express my gratitude to Prof. Dr. Erik Demeulemeester, Prof Dr. James H. Patterson, Prof Dr. Roman Slowinski, and Prof Dr. Ramon Alvarez-Valdes for the valuable help they provided with suggestions, papers, and computer programs.I, As to the technical realisation of this book, lowe thanks to Reimer Karlsen for coding and impl~menting parts of the algorithms, to Marc Schumann for drawing all figures, to Ina Kantowski who looked after the literature, and to Uwe Penke for providing a ready-to-use computer-laboratory. The gratitude that I feel towards my family requires no further comments.
