Production designer is a term used in the movie industry to refer to the person with the responsibility for designing the sets and costumes and choosing locations, and thus for creating the overall visual appearance of a film. In the preparation phase, the director has already begun work with the set unit, or production design unit. This is headed by a production designer's supervision, an art director supervises the construction and painting of the sets. The set decorator, often someone with experience in interior decoration, modifies the sets for specific filming purposes, supervising a staff who finds props and a set dresser who arranges things on the set during shooting.