Interior designers make indoor spaces functional, safe, and beautiful by determining space requirements and selecting essential and decorative items, such as colors, lighting, and materials. They must be able to draw, read, and edit blueprints. An interior designer's minimum task is to define the design and ensure the safe performance of a space. They should plan the space to maximise the function and movement within it, as well as taking airflow, heat, extraction, electrical and plumbing regulations into account.