1 December 2025 5 December 2025 United States The Interservice/Industry Training, Simulation and Education Conference (I/ITSEC) is the world's largest modeling, simulation and training event. Held near the beginning of December in Orlando, Florida, USA, I/ITSEC consists of peer-reviewed paper presentations, tutorials, special events, professional workshops, a commercial exhibit hall, a serious games competition, and STEM events for teachers and secondary students.