PEGEM is an end-to-end, fully integrated simulation tool, developed for the U.S. Army Space and Missile Defense Command by BAE Systems to compute the ground effects from intercepted or non-intercepted intended releases of a missile carrying conventional, chemical, biological warheads, or weapons of mass destruction.

PEGEM helps (1) determine the effectiveness of anti-missile systems under the development of the US Government, (2) assist in the defensive planning for simultaneous missile attacks, and (3) optimize civilian and military operational effectiveness through planning, exercise involvement, consequence management, and simulation.

Engagement of the threat missile, even if resulting in a "hit", can result in ground effects that rival in severity a non-intercepted target. Mission success depends on thorough information and analysis.