XPRESS is a solver Engine, for use inside and outside Microsoft Excel. The XPRESS Solver is an extraordinarily powerful, field-installable Solver Engine that “plugs into” Risk Solver Platform and Premium Solver Platform for Excel, and takes advantage of its new Polymorphic Spreadsheet Interpreter. It handles with linear programming problems with up to millions of variables and constraints, with no fixed limits on problem size. It also solves mixed-integer linear (LP/MIP) problems with astonishing speed. And with the Newton Barrier Solver option, it solves large, challenging quadratic programming (QP) and mixed-integer quadratic (QP/MIP) problems with extraordinary speed.