The volume comprises a collection of 172 extented abstracts of talks presented at the 16th Symposium on Operations Rese- arch held at the University of Trier in September 1991. It is designated to serve as a quickly published documentation of the scientific activities of the conference. Subjects and areas touched upon include theory, modelling and computational methods in optimization, combinatorial op- timization and discrete mathematics, combinatorial problems in VLSI, scientific computing, stochastic and dynamic opti- mization, queuing, scheduling, stochastics and econometrics, mathematical economics and game theory, utility, risk, insu- rance, financial engineering, computer science in business and economics, knowledge engineering and production and ma- nufacturing.