In 1976, Keith Johnstone and a group of his students formed the Secret Impro Group to perform noon-hour shows at the University of Calgary. The following summer they regrouped to form The Loose Moose Theatre Company, which is currently at the center of the theatrical activity known as TheatreSportsTM, a format which has spread to over 22 countries.

Johnstone created TheatreSportsTM as a response to two main concerns. The first was the audience. Why, he wondered, did things like sporting events draw so well while theaters were half empty? Could it be that the connotations of "culture" kept people away? People would go to a football game without knowing beforehand if it would be a good game; they were, however, assured of excitement and the opportunity to participate, to vocalize, and to invest something of themselves in the event and the outcome. Keith would speak of envying the "passion" of a sports audience. The goal, and the result, of TheatreSportsTM is to attract people who wouldn't normally go to the theatre. Johnstone was also concerned about the performers. He wanted TheatreSportsTM to provide training for improvisation. It would help in recruiting new performers, and its structure would allow for a greater number of participants.