Final answer:
The Stage Directors and Choreographers Society (SDC) is the union that represents the director in professional theater productions.
Step-by-step explanation:
The union that represents the director in a professional theater production is the Stage Directors and Choreographers Society (SDC). SDC is a labor union that represents stage directors and choreographers, advocating for their rights and ensuring proper compensation and working conditions. They negotiate contracts and wages on behalf of directors.
For example, a theater director working on a Broadway production would be a member of SDC, which would provide legal representation and negotiate their contract, wages, and benefits. It is important to note that the director is responsible for the artistic aspects of the production, while the producer handles the administrative and financial aspects.