It includes Gordon Stephenson House, named in honour of Gordon Stephenson, an architect responsible for planning much of modern Perth's urban form through the 1955 Plan for the Metropolitan Region, Perth and Fremantle.

[1][2] It currently houses the government departments of Planning, Lands & Heritage,[3] Transport[4] and Mines, Industry Regulation & Safety,[5] and various other offices.

[7] The land for 140 William Street had been acquired by LandCorp in 2003 and 2004 for the construction of Perth Underground station.

As an incentive, the state government committed to a 15-year lease of 22,000 square metres (240,000 sq ft) of office space within the future development.

[11][14] The Evolution Consortium was chosen as the preferred proponent in September 2006,[15][16] and by December 2006, the contract had been signed and the design revealed.