CAE's GESI is a constructive simulation system designed to run complex and comprehensive joint and combined exercises at both tactical and operational levels. CAE GESI is optimized for use for both computer-assisted exercises (CAX) as well as classroom education and training. Land units are typically represented from the company to division level. In CAX mode, the CAE GESI system enables commanders and their staff to conduct normal training exercises in their regular command posts using live command and control systems. The commanders determine the course of the simulated combat scenario exercise by the decisions they make. Using regular tactical maps or command and control (C2) systems, the commanders receive situation reports from subordinate commanders at the CAE GESI workstations. The CAE GESI system is then used to represent the mission area, including entities such as vehicles, aircraft, ships, logistics, casualties and more.
CAE GESI is the primary constructive simulation training tool used for command and staff training in Europe. Whether preparing for traditional combat readiness, operations other than war (OOTW), peacekeeping and humanitarian assistance, civil and military cooperation (CIMIC), military operations in urban terrain (MOUT), or joint and multinational operations, military leaders are trained with CAE GESI in procedures, processes and decision-making to help ensure mission readiness. Even though every country calls its GESI system differently, for example, SIRA in Germany, KESI in Finland, or NASCT in Norway, they are all based on the same constructive simulation software: CAE GESI.