The director is responsible for interpreting the playwright's work through the cast with the help of the staff. It is the director's artistic concept of the play that the cast, staff, and crew work to obtain.
There is no definitive list of the duties of a stage manager that is applicable to all theaters and staging environments. Regardless of specific duties, however, the stage manager is the individual who accepts responsibility for the smooth running of rehearsals and performances, on stage and backstage.