Final answer:
The main purpose of costume design in theatre is to support the story and help the audience understand the characters, which is achieved by collaborating with directors and other designers, conducting research, and creating detailed costume designs.
Step-by-step explanation:
The overall purpose of costume design is similar to that of the set designer in that both roles are essential in creating a unified visual appearance for a theatre production that supports and enhances the story being told.
Costume designers collaborate closely with the director and other design team members to decide on the play's concept, including potential time periods, themes, and level of realism.
Through their designs, costume designers convey critical information about each character, such as their age, social status, personality, and relationship to others, while considering the play's setting and other design elements like lighting and scenery.
Once a concept is established, the costume designer engages in visual research, followed by the creation of costume renderings or research boards to guide the costume technicians in realizing each costume.
During this process, several considerations come into play, including budget constraints, stock availability, and the practicality of building, buying, or renting costume pieces.
The ultimate goal of the designer is to ensure that the actors feel authentic in their roles and that the audience can understand the characters' stories through their clothing, which should appear as natural attire rather than costumes.