Operations research (OR) is a discipline explicitly devoted to aiding decision makers. A number of closely related fields are management science, decision science, operations management, and systems engineering. OR is most often taught in undergraduate engineering and business programs. It is often a component in industrial engineering curricula. There are a number of graduate programs and a few undergraduate programs in OR. The professional society for OR in the United States is INFORMS, the Institute for Operations Research and the Management Sciences. A definition of OR taken in part from the INFORMS web site is:

OR Professionals aim to provide rational bases for decision making by seeking to understand and structure complex situations and to use this understanding to predict system behavior and improve system performance. Much of this work is done using analytical and numerical techniques to develop and manipulate mathematical and computer models of organizational systems composed of people, machines, and procedures.

Additional information and examples of OR applications can be found at the Science of Better web site sponsored by INFORMS.

In this section we provide definitions of OR terms, a description of the OR process and an article relating Excel Models to OR. Some of the material in this section is based on Chapter 1 of Operations Research Models and Methods.