The “elephant in the room” of press simulation. Historically, experienced formulators expect “simulator data” to be different to “production press data”. It looks different due to the different shape of the load curve! In practice, tableting loads are high, and production presses are an assembly of elastic components. Contact faces deform and metals stretch and bend, and always more than simplistic calculations would predict. Compaction Simulators have historically simulated presses based on theoretical geometrical dimensions, assuming the press is infinitely stiff. This gives a higher strain rate, a shorter dwell, and a higher load release rate than on a production press, and therefore a different “shape” to the load curve. The Huxley Bertram Compaction Simulators are the first to give a “Press Elasticity Simulation” capability. This is a major step forward in simulation accuracy, and will lead to greater confidence in scaling up products for production. Studies of the relative behaviour of different production presses can now be meaningful, and especially the comparison of pilot scale and production scale presses. Trouble-shooting of production issues will be performed more effectively.