Several important decisions must be made about the plan of the production before much else moves forward. One major decision is whether the film will be made under the auspices of all of the film-related unions and guilds, just some of them, or none of them.
A union is a collective bargaining group. In the case of film unions, the idea is that the union represents Labor, and negotiates or bargains with Management about working conditions (hours worked, benefits, grievance procedures, and salaries.)
1. the cast, stunt people, singers, dancers, and background actors, all represented by the Screen Actors Guild (SAG);
2. the writer, represented by the Writers Guild of America (WGA);
3. the director, production ...