This volume contains 40 papers on econometric decision models. These are optimization models, the constraints of which consist, above all, of econometric equation systems. Based on macrodata or microdata, they are major instruments for studying economic and social policy at various levels of aggregation. The papers are arranged in 10 parts, with such topics as optimal control, multicriteria decision-making (vector optimization), constructing scalar-valued objective functions, rational expectations, models, co-integration estimation and testing, structural and sensitivity analyses, modelling of environmental and energy problems, and performance in policy analyses. Probably the most distinctive feature of this proceedings volume is that it also contains reports about several attempts to construct scalar-valued objective functions by means of economic methods.