Fourteen years later, Lewis wrote Moneyball: The Art of Winning an Unfair Game (2003), in which he investigated the success of the Oakland Athletics baseball team and their general manager Billy Beane.

[12] Lewis has worked for The Spectator,[2] The New York Times Magazine, as a columnist for Bloomberg, as a senior editor and campaign correspondent to The New Republic,[13] and a visiting fellow at the University of California, Berkeley.

Lewis worked for Conde Nast Portfolio, but in February 2009 left to join Vanity Fair, where he became a contributing editor.

[16][17] During 2013 in Vanity Fair, Lewis wrote on the injustice of the prosecution of ex-Goldman Sachs programmer Sergey Aleynikov,[18] who is given an entire chapter in Flash Boys.

[21] In 2016, Lewis published The Undoing Project, chronicling the close academic collaboration and personal relationship between Israeli psychologists Amos Tversky and Daniel Kahneman.

The duo found systemic errors in human judgment under uncertainty, with implications for models of decision-making in fields such as economics, medicine, and sports.

In September 2018, The Guardian published an excerpt from the book, using a quote by Trump advisor Steve Bannon in its title: "This Guy Doesn't Know Anything".

[29] The first season comprised seven episodes, each taking on a different aspect of society addressing the concept of fairness "in realms ranging from art authentication to consumer finance".

"[33] Against the Rules is produced by Pushkin Industries, the media company founded by journalist Malcolm Gladwell and former Slate executive Jacob Weisberg.

[34] In a review of Moneyball, Dan Ackman of Forbes said that Lewis had a special talent: "He can walk into an area already mined by hundreds of writers and find gems there all along but somehow missed by his predecessors".

[35] A New York Times piece said that "no one writes with more narrative panache about money and finance than Mr. Lewis", praising his ability to use his subject's stories to show the problems with the systems around them.

At a House Financial Services Committee hearing in April 2014, Mary Jo White, a former Wall Street insider (as a Debevoise & Plimpton lawyer primarily for Wall Street financial firms)[38] who later served as the U.S. Securities and Exchange Commission (SEC) Chair, denied the book's premise, saying, "The markets are not rigged".

[39] In June 2014, White announced that the SEC would undergo a new round of regulatory review in response to concerns about dark pools and market structure.

[50][51] In 2021, their middle child, daughter Dixie, was a passenger in a head-on collision with a semi truck near Truckee, California; the driver, her boyfriend, had inexplicably crossed the median.