One National Circuit Barton is the 15,000sqm headquarters of the Department of the Prime Minister and Cabinet. When you enter, your gaze is drawn upward to view the full five stories of the building and the light steel and glass stair. The stair is suspended from the roof with slim steel rods and passes through the central hub on each floor, forming the vertical heart of the building. Shared facilities such as meeting rooms are located in this hub. Each floor provides two secure work wings where staff enjoy a modern, spacious and flexible environment filled with natural light.

A key feature of the design is the striking use of colour and pattern. Colour gives a signature to each floor while pattern creates cohesion of the interior fitout. Light playfully reflects the transparent colours creating a kaleidoscope effect. The interior fitout is about breaking down the visual effect of security requirements and allowing a department to be seen at work. The interior provides an interactive environment that matches the visionary shift for the Department of the Prime Minister and Cabinet. Together, the interior fitout and the building itself set a benchmark for other government departments.