The performers in any stage presentation must have clothing to match their roles, so theater productions often hire a wardrobe person. Their responsibilities are many before and during the shows, and their job is to design, sew and individually fit each outfit the performer will wear. It takes time to do this, and their work must be complete well before the show opens. It would be difficult enough to produce one outfit for each cast member, but some of them will require multiple changes of clothes.
Designing the outfits to be worn during the performance is the responsibility of the wardrobe department, but each selection must be approved by the director. Once the choices are made, the materials are bought and the cutting and sewing begins. If a performer has not yet been chosen for the role, their outfits will be fitted and alterations made at a later date. If there is an understudy for the role, that person must also have a set of the same outfits.
Clothing designed for a performance is not worn on the street, but it must stand up to a great deal of wear and tear. Many companies perform matinees as well as evening shows, and they use their entire wardrobe for each show. Cleaning and repairs are also taken care of by the wardrobe department, so they must ensure they have the ability to keep each piece in good working order. They do not want the burden of repairing an outfit after every performance, and they tend to choose materials that are easy to keep clean.
While the clothes are worn only for performances, the quality of each outfit must be very good. Performers need to be comfortable while they move on stage, and this includes any dancers as well as the regular cast of the show.