Janette Sadik-Khan was appointed commissioner of the New York City Department of Transportation in 2007. For six years, she managed nearly 5,000 employees and was responsible for the operation and management of some 6,300 miles of streets throughout the city's 5 boroughs.

Despite her access to a budget of some $2 billion, Sadik-Khan adopted a designer's approach to urban innovation: rapid testing and regular iteration. In other words, try an idea to see if it would work; if it didn't, try something else, no harm done. In Times Square, an iconic New York City location visited by 350,000 people every day, this involved the creation of pedestrian zones by painting the asphalt and putting up some lawn chairs. The success of the approach allowed her to create 50 pedestrian zones throughout the city, in the process repurposing 26 acres of space previously allocated to cars.

In 2013, she helped to introduce the instantly-popular Citi Bike bicycle-sharing program to the city, making New York one of the cycling capitals in the United States.