In "The New New Thing" (1999), he investigated the then-booming Silicon Valley and discussed obsession with innovation. Four years later, Lewis wrote "Moneyball" (2003), in which he investigated the success of Billy Beane and the Oakland Athletics. In August 2007, he wrote an article about catastrophe bonds, entitled "In Nature's Casino", that appeared in "The New York Times Magazine". Lewis has worked for "The Spectator", "The New York Times Magazine", as a columnist for Bloomberg, as a senior editor and campaign correspondent to "The New Republic", and a visiting fellow at the University of California, Berkeley. He wrote the "Dad Again" column for "Slate". Lewis worked for Conde Nast Portfolio, but in February 2009 left to join "Vanity Fair", where he became a contributing editor. In September 2011, after the successful release of the film adaptation of his book "Moneyball", it was reported that Lewis planned to take on "a much more active role in the what could be the next film based on one of his books" and would start writing a script for a "Liar's Poker" film. During 2013 in "Vanity Fair", Lewis wrote on the injustice of the prosecution of ex-Goldman Sachs programmer Sergey Aleynikov, who is given an entire chapter in "Flash Boys". "Flash Boys", which looked at high-frequency trading of Wall Street and other markets, was released in March 2014. In 2017, Lewis wrote a series of articles for "Vanity Fair" in which he described the Trump administration's approach to various federal agencies, including the Department of Energy and the Department of Agriculture. His articles described a sense of incredulity and disillusionment from career civil servants, particularly because of the lack of attention from the Trump administration over the importance of some of their work, and the lack of care, knowledge, experience, and respect from Trump political appointees. That material was incorporated into his book entitled, "The Fifth Risk", which remained on the New York Times best seller list for non-fiction for fourteen weeks, and described the disconnect between the well-prepared plans for transition by the Obama administration and the apparent failure of concern by the incoming Trump administration and his appointees. Along with Energy and Agriculture, this book added Commerce among the main departments described. In September of 2018, a lengthy excerpt from the book was published by The Guardian that used a quote by a top adviser to Trump in its title, and the excerpt was republished again among a review of the most popular articles of the entire year.