Abstract: The Interactive Media Laboratory at Dartmouth Medical School produces computer games and multimedia programs for public health preparedness. With Department of Homeland Security funding, the IML is developing the Virtual Terrorism Response Academy, which uses game technology to prepare first responders for rescue efforts in which hazardous materials may be involved. This paper looks at the history of the “Virtual Clinic” concept and the original rationale for creating what Max Boisot calls “epistemology space.” It also offers an account of the VRTA designers' responses to potential criticism from learning specialists in game studies who object that the game is too didactic and discourages trial-and-error by restraining the learner in the narrative conceit of a “simulation of a simulation.”.