Chicago Mayor Rahm Emanuel walks from the train station to his City Hall office.

Photograph by Thomas Prior for Bloomberg Businessweek

Chicago Mayor Rahm Emanuel walks from the train station to his City Hall office.

Photograph by Thomas Prior for Bloomberg Businessweek

Rahm Emanuel at Work in Chicago

Chicago Mayor Rahm Emanuel walks from the train station to his City Hall office.

Photograph by Thomas Prior for Bloomberg Businessweek

The door to the mayor’s office.

Photograph by Thomas Prior for Bloomberg Businessweek

Emanuel on Chicago’s mass transit infrastructure: “We have dramatically increased our investment. ... Given that I think outside of New York we have the highest ridership on a mass transit system, it’s in our economic self-­interest to make investments.”

Photograph by Thomas Prior for Bloomberg Businessweek

In his office, the mayor talks with Bloomberg Businessweek’s Devin Leonard.

Photograph by Thomas Prior for Bloomberg Businessweek

A wall of portraits of former mayors of Chicago.

Photograph by Thomas Prior for Bloomberg Businessweek

Emanuel in front of City Hall.

Photograph by Thomas Prior for Bloomberg Businessweek

A view of Chicago from a CTA Brown Line train.

Photograph by Thomas Prior for Bloomberg Businessweek

The mayor on the El on his way to work in the morning.

Photograph by Thomas Prior for Bloomberg Businessweek