Chetwynd has worked as a staff reporter for USA Today, The Hollywood Reporter and U.S. News and World Report. His writing has also appeared in such publications/websites as The Wall Street Journal, The Times (of London), Chicago Tribune,, Harvard Negotiation Law Review, The Observer Sport Monthly, and Variety. He’s a two-time winner of the Los Angeles Press Club Award for best newspaper article written by a correspondent (1999 and 2000).

He has written seven books and contributed chapters or essays to four others:

  • "Totally Scripted: Idioms, Words, and Quotes from Hollywood to Broadway That Have Changed the English Language" (Lyons Press, 2017)
  • "The Field Guide to Sports Metaphors: A Compendium of Competitive Words and Idioms" (Ten Speed/Penguin Random House, 2016)
  • “The Book of Nice: A Nice Book About Nice Things for Nice People” (Workman, 2013)
  • “How the Hot Dog Found its Bun: Accidental Discoveries and Unexpected Inspirations That Shape What We Eat and Drink” (Lyons Press, 2012)
  • “The Secret History of Balls: The Stories Behind the Things We Love to Catch, Whack, Throw, Kick, Bounce and Bat” (TarcherPerigee/Penguin Random House, 2011)
  • “Baseball in Europe: A Country by Country History” (McFarland & Co., 2008)
  • “British Baseball and the West Ham Club: History of a 1930s Professional Team in East London” (McFarland & Co., 2007). It was co-written with Brian A. Belton.
  • Contributions: "Baseball without Borders: The International Pastime" (University of Nebraska Press); "West Ham United Miscellany" (Pennant Books); "Nine Aces and a Joker" (Fine Leaf)' "Baseball Beyond Our Borders: An International Pastime" (University of Nebraska Press).
Success for his books has included "How the Hot Dog Found Its Bun" reaching number 13 on the New York Times Best Seller charts (ebooks/non-fiction) in 2015; "The Book of Nice" winning the IndieFab Award for best popular culture book in 2013; and "The Secret History of Balls" being named an NPR best book in 2011.

In the broadcasting world, Chetwynd has served as the BBC’s color commentator for the World Series five times (2003-2005, 2011-2012), providing live on-site analysis as part of a two-person play-by-play team. He also co-hosted BBC Radio 5 Live Sports Extra’s weekly coverage of Major League Baseball during the regular season (2010-2013). In addition, between 2002 to 2008, Chetwynd was a baseball analyst for the British television network Channel 5. He also spent a season as the host on C5's Monday Night Football coverage of the NFL. Chetwynd did voice over work for sports packages on Five's sister digital station Five US between 2006 and 2008 as well. In November 2013, he started hosting and producing "The Real Deal in Sports" on KGNU radio (88.5 FM/1390 AM in the Denver-Boulder area). The public affairs show examines the cultural, social, political, spiritual and economic impact of sports on the world at large.

Chetwynd is also a former baseball player. His career included stints at the NCAA Division I college level, professional baseball in the United States and Europe, and international play for Great Britain. He played collegiately at Northwestern University in the Big Ten Conference and was named to Academic All Big Ten teams twice as a catcher. He was also a two-time receipient of Northwestern baseball's Jack Dempsey Team Award, which was given annually for leadership, service and commitment to the team. Following graduation in 1993, he signed a professional contract with the Zanesville Greys in the independent Frontier League.

In 1996, he began a 10-year career as a member of Great Britain's national baseball team. (Chetwynd was born in London, England.) He would represent GB in five European Championships (1996, 1999, 2001, 2003, 2005) and one Olympic Qualifier (for the 2000 Sydney Games). In 2002, he was named a “Sporting Champion” by Sport England. This program was created to give children positive role models in athletics. He also played a season as a professional in Sweden's Elitserien, helping Oskarshamn to a share of the regular season title in 2003. In 2014, Chetwynd was inducted into the British Baseball Hall of Fame for his on-field performance and off-the-field contributions to the sport in Great Britain.

Other jobs in baseball have included serving as the general manager for the South African team at the 2009 World Baseball Classic; working as a communications executive in Major League Baseball's London office; and brokering contracts with Major League teams on behalf of international amateur free agents from non-traditional baseball countries. In 2013, as a player's representative, he negotiated the largest contract ever signed by a European amateur player with a Major League club ($1.3 million signing bonus).

Chetwynd also competes in the Olympic sport of curling. In the 2016-2017 season, his team qualified for the U.S. National Curling Championships, placing ninth in the United States.

He holds two degrees in journalism (BSJ and MSJ) from Northwestern. He earned a JD (cum laude) from the University of Arizona, where he received the Dannie Lee Chandler Award for writing and research on the First Amendment. He also obtained an LL.M. (merit) from the London School of Economics and Political Science (LSE). For his work at the LSE, he was given the Brian Keelan Memorial Prize for excellence in the study of dispute resolution in a commercial context. He's a member of the Bar in the District of Columbia and the state of New Mexico.

He’s married with two children.