World Theater Day is observed worldwide every March 27 and celebrates the importance of theater as a complex art form. Established by the International Theater Institute (ITI) and supported by UNESCO, the first celebration took place in 1962, coinciding with the opening of the Theater of Nations season in Paris. The idea was proposed by Arvi Kivimaa, director of the Finnish ITI Center. Each year, an International Message is written by a notable figure in the performing arts, with the inaugural message authored by French playwright and filmmaker Jean Cocteau. The day is marked by various performances and events that highlight the collaborative efforts of playwrights, directors, actors, and composers in the theater community.