Simulations have long been used in business management generally and in the tourism and hospitality industry in particular. They have been employed in business planning, policy making, decision support, gaming, and, notably, with considerable success TandL. In addition, they have been developed to support planning and operations at the individual, enterprise, tourism destination, state, national, regional, and international levels. In short, there is hardly an area of the tourism and hospitality industry nor any category of involved party left untouched by the rapidly expanding array of simulations currently available. In this chapter, the history and range of tourism and hospitality simulations is reviewed, with an emphasis on those constructed using system dynamics and agent-based modelling approaches. In common with an increasing number of researchers, we believe that there is considerable advantage to be gained from a combined system dynamics and agent-based approach, and we present a detailed example of one such tourism TandL simulation game. The motivation behind the game’s development, the research approach (design science) that informed its development, design, construction, and validation are all discussed.