A Canadian Naval threat/countermeasures simulator (NTCS) capable of modeling the engagement between a naval ship and an infrared (IR) guided anti-ship missile is presented. The NTCS program is built upon previously developed naval ship signature software entitled Ship Infrared Simulator (SHIPIR) which produces 3-D graphical imagery of a ship in its sea/sky background for a wide range of operational, atmospheric, observer, and spectral conditions. By adding models for an IR seeker head, missile flight dynamics and commonly deployed ship IR countermeasures, NTCS can effectively assess the IR susceptibility of naval platforms through calculation of target lock-on ranges and hit/miss distances. Current and future naval ships can be analyzed for IR suppression effectiveness in such areas as hot surface visibility, low emissivity paints, and engine exhaust signature suppression. The various deployable countermeasures (flares, smoke screens, washdown, and ship maneuvers) and missile/seeker heads modeled in NTCS permit the assessment of ship survivability and development of tactics and counter-measures necessary to provide adequate IR protection. A description of NTCS is provided with emphasis on the missile and countermeasure models and overall engagement simulation. Some sample simulations to date on the Canadian DDH-280 tribal class destroyer are presented.