Gurobi Optimizer is a mathematical programming solver from Gurobi Optimization, Inc. The program provides users with tools to optimize solutions for quadratic programming (QP), quadratically constrained programming (QCP), mixed-integer quadratic programming (MIQP), mixed-integer quadratically constrained programming (MIQCP), mixed integer linear programming (MILP), and linear programming (LP). The latest version (5.1) features optimization algorithms with fast and proven optimality on mixed-integer programming models. It has flexible interfaces and supports a large number of programming languages like matrix-oriented interfaces for R, C, and MATLAB, and object-oriented interfaces for C++, .NET, Python, and Java. It provides maximum productivity to users by supporting links to modeling languages like AMPL, MPL, GAMS, and AIMMS, and links to Excel through Risk Solver Platform and Premium Solver Platform. Significant improvements on mixed-integer programming (MIP), numerical robustness, user control of the random number seed, and updated platform support are some of the enhanced features in the latest version. The supported platforms are Windows 8, Mac OS, X, Python 2.7, SuSE 12, and RHEL 6.3.