To build the world's tallest building, it takes an office fit for big ideas

The first thing to know about Adrian Smith and Gordon Gill is that they’re not afraid of heights. Their firm, AS+GG, recently won a competition to design a tower in Jeddah, Saudi Arabia, that’ll reach a full kilometer into the sky. For those who aren’t good with the metric system, that’s 2½ Willis towers. Once the construction is complete, Smith will break his own record: He’s also responsible for the 2009 construction of Burj Khalifa in Dubai, which is currently the tallest skyscraper in the world.

Their 13,000-square-foot 111 W. Monroe perch has seen its fair share of tenants since it was built in 1958. Girded with stainless steel and marble, their office originally served as the main boardroom and dining area for Harris Bank heir and chairman Stanley Harris. Since then, it’s served time as the Monroe Club, an executive dining area for bankers and a hub for dot-com companies. AS+GG took over in 2006.

Photos by Sara Mays