Exercises should be as realistic as possible while remaining logistically feasible Taken together, the optimal mix of design elements represents a balance between exercise objectives and logistic feasibility. The ideal balance is one that assures sufficient realism to provide a meaningful experience while minimizing distractions associated with the necessary artifice of exercise scenarios. Some departures from reality may be inadvertent if scenarios are developed with insufficient attention to local routines, forcing participants to sidestep usual procedures. Even seemingly minor design errors, such as using an outdated name for a hospital, or a time course for a disease that is inconsistent with its known epidemiology, can undermine the credibility of the exercise and can distract participants enough to take them out of their roles, thus disrupting the flow of the exercise.