The sixth International Symposium on the Analytical Hierarchy Process (AHP) is the first one to take place in Europe.SInce the first symposium in Tianjing, PR of China, in 1988-more than 13 years ago-theory has progressed due to work of researchers all over the world. The same can be stated concerning practical applications which are now in use in hundreds of areas. More than 30 years ago Thomas L. Saaty developed the analytic Hierarchy Process (AHP) and nowadays the Analytic Hierarchy Process is probably the most used technique in multi-criteria-decision-making. People from over 30 countries around the world have travelled to Switzerland. A central purpose of the symposium is to deepen the participants' understanding of the analytic Hierarchy Process and the Analytic Network Process (ANP).