Simulation has become a critical aspect of medical education. It allows health care providers the opportunity to focus on safety and high-risk situations in a protected environment. Recently, in situ simulation, which is performed in the actual clinical setting, has been used to recreate a more realistic work environment. This form of simulation allows for better team evaluation as the workers are in their traditional roles, and can reveal latent safety errors that often are not seen in typical simulation scenarios. We discuss the creation and implementation of a mobile in situ simulation program in emergency departments of three hospitals in Tuscany, Italy, including equipment, staffing, and start-up costs for this program. We also describe latent safety threats identified in the pilot in situ simulations. This novel approach has the potential to both reduce the costs of simulation compared to traditional simulation centers, and to expand medical simulation experiences to providers and healthcare organizations that do not have access to a large simulation center.