During October’s Engineering Simulation for Military Technology Conference, just outside Washington, D.C., there was much discussion of the tools and techniques for simulating the depth of the design V — from requirements planning, through system of systems, through systems to full physics-based simulation. A clear standout theme from the presentations and interactions was an increasing convergence of these different scales of tools. From the top level there is downward pressure to incorporate increased fidelity in the models used to support the systems view and that this needs to be derived from a physics-based understanding. From the lower levels there is upward pressure to extract physics-based reduced-order models and robust design envelopes that can be used to feed into higher-level systems models. This is moving beyond the realm of discussion and is becoming reality. One example of real-world application is the use of physics-based simulation to develop better helicopter flight simulators — in effect simulating the simulator!  Watch and listen to the team at the University of Liverpool in the U.K. talk about this work.