The International Alliance of Theatrical Stage Employees, Moving Picture Technicians, Artists and Allied Crafts of the United States, Its Territories and Canada, known as simply the International Alliance of Theatrical Stage Employees, is a North American labor union representing over 168,000 technicians, artisans, and craftspersons in the entertainment industry, including live theatre, motion picture and television production, broadcast and trade shows in the United States, its territories, and Canada. Wikipedia