The most important and most abused person in Hollywood. The screenwriter writes the script that provides the foundation for the film, though it may go through any number of changes, both in the rewriting process before production, during production, and in the editing process afterward. While in the world of theater, there is usually only one playwright on any given play (or one collaborative team), in film there may be many screenwriters throughout the life of a project.

Writes a script, either from an original idea or from an existing book or story.

Screenwriters, scenarists or script writers, are authors who write the screenplays from which movies and television programs are made. Many of them also work as "script doctors," attempting to change scripts to suit directors or studios; for instance, studio management may have a complaint that the motivations of the characters are unclear or that the dialogue is weak.