For more than a decade US Army CERDEC Night Vision and Electronic Sensors Directorate (NVESD) has been developing real-time imaging infrared sensor simulations to aid the Army in: sensor design, prototyping, and analysis; search and target acquisition (STA) model development; and evaluation of tactics, techniques and procedures. In recent years, the sensor simulation program has undergone significant programmatic and technical changes, while still seeking to deliver simulation tools to the Army. This paper provides an update on the current state of NVESD simulation capabilities, the technical vision and the simulation validation efforts. Topics to be discussed include the transition of software to the PC platform, an explanation of the principle software products, and a look at future validation experiments and software enhancements.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.