Before anyone can begin building the set, they need to know what to build. The show's designer will bring a concept, ideas about the kind of mood they want and picture references. They work with the Drawing Office to refine their ideas, based on practical factors such as available resources and the shape of the stage.
The Drawing Office costs up the design. They need to consider if the show will be in rep with another show – with different shows alternating so the set has to come in and out on a daily basis. Sets for shows in rep need to be easily removed and stored, and robust enough to last for all performances. All sets need to meet strict criteria for safety and sustainability.
They work with the designer to create the model box – a 1:25 scale model of the set which is used by all the technical departments. They create drawings for every object of scenery you see on stage, showing not only what an item should look like, but also exactly how to construct it. There can be hundreds of drawings by the time the actors take to the stage.