The OR Society (The Operational Research Society)

CORMSIS (Centre for Operational Research, Management Science and Information Systems)

INFORMS (The Institute For Operations Research and The Management)

ACM (Association for Computing Machinery)

EURO (Association of European Operational Research Societies)

IFORS (International Federation of Operational Research Societies)

IIE (Institute of Industrial Engineering)

LANCS: The LANCS Initiative is built on a collaboration between four U.K. Universities: Lancaster, Nottingham, Cardiff and Southampton. The principal aim is to strengthen and grow theoretical Operational Research in the UK with a particular emphasis on deepening our theoretical understanding of complex and uncertain real world problem solving environments.

AIMMS is an advanced development environment for building optimization based operations research applications and advanced planning systems.

GAMS (General Algebraic Modelling System) is a high-level modelling system for mathematical programming and optimization. It consists of a language compiler and a stable of integrated high-performance solvers.

ILOG Optimization uses mathematical models for addressing problems to create the plans and schedules that best meet the goals within specified resources. Tradeoff explorations, what-if analysis, and scenario planning close the loop back to the inputs and model.

LINDO Systems has been a leader in providing fast, easy to use tools for mathematical optimization. LINDO Systems have developed four systems to solve linear programming models: LINDO and the LINDO API to solve linear programming models and LINGO and What'sBest! to solve nonlinear and linear problems.

Gurobi Optimizer is a commercial software package for solving large-scale mixed-integer linear optimization problems. Gurobi is named for its founders: Zonghao Gu, Edward Rothberg and Robert Bixby; Bixby was also the founder of CPLEX, while Rothberg and Gu led the CPLEX development team for nearly a decade.

Maximal Software, Inc. is a leading provider of software for developing and formulating models in the field of optimization. Maximal is the developer of the MPL Modeling System and the OptiMax 2000 Component Library.

Xpress-Optimizer The Xpress-Optimizer is a Linear and Integer Programming optimizer which has been carefully programmed to take full advantage of matrix structure.

Ziena is a leader in optimization software and solutions. It was founded in 2001 to develop and sell KNITRO, the industry's best nonlinear solver. It also distributes the AMPL (A Modelling Language for Mathematical Programming) modeling environment for optimization, provides modeling assistance, and software integration expertise.