Roman Mars
Roman Mars is an American radio producer. He is the host and producer of 99% Invisible, a KALW radio show and podcast, and a founder of the podcast collective Radiotopia, which he describes as efforts "to broaden the radio landscape make shows that aren't bound by conventions" of public radio in the United States. In 2020, he co-authored the New York Times best seller The [99% Invisible City] with Kurt Kohlstedt.
He has also contributed to radio programs Radiolab and Planet Money. Fast Company identified him as one of the hundred most creative people of 2013. Mars, with Elizabeth Joh, also hosts the podcast What Roman Mars Can Learn About Con Law.
Early life
Mars left a PhD program in genetics to undertake an unpaid internship at public radio station KALW in San Francisco.In 2004, he produced a program called Invisible Ink on KALW.
''[99% Invisible]''
Mars and his radio show, 99% Invisible, have been credited in the mainstream press as an innovative form of radio production, defining a new movement of independent radio and podcast creators. In 2016, Mars and Justin McElroy used asynchronous podcasting, a method where each person recorded their portions separately and later combined them to create a podcast episode. This new technique was used to create the first episode of Smart Stuff, which started with My Brother, My Brother and Me episode 316 and was completed in 99% Invisible episode 225.99% Invisible Inc., the company that produces 99% Invisible, was sold to Sirius XM's Stitcher Radio in April 2021. Mars donated $1 million from the sale to Radiotopia.
Books
In October 2020, Mars and 99pi digital director Kurt Kohlstedt released The 99% Invisible City, a non-fiction book that functions as a field guide to the built environment. Mars noted that the book allowed the team to explore visual stories that were difficult to convey in a purely audio format. The book debuted on the New York Times Best Seller list for hardcover non-fiction.Radiotopia
In partnership with the Knight Foundation and the Public Radio Exchange, Mars also created the podcast collective Radiotopia.The Public Radio Exchange has hired Mars to curate a radio program called Remix, which is syndicated by at least 14 public radio stations across the US. In June 2017, Roman Mars began cohosting the constitutional law podcast What Trump Can Teach Us About Con Law with Elizabeth Joh, a professor of the subject at University of California, Davis, School of Law. The show later left Radiotopia and is now distributed as What Roman Mars Can Learn About Con Law alongside 99% Invisible as part of SiriusXMref name="Conlawsite" />
''[What Roman Mars Can Learn About Con Law]''
In June 2017, Mars launched What Trump Can Teach Us About Con Law, an educational podcast co-hosted with Elizabeth Joh, a professor at the University of California, Davis School of Law. The series analyzes the United States Constitution through the framework of modern executive actions and legal controversies. The show launched without prior announcement, yet quickly reached the top of the podcast charts and surpassed 100,000 downloads within days.The podcast has been cited by the Nieman Foundation for Journalism and Oxford University Press as a defining example of "civic mediation," noted for its ability to translate complex legal theory for general audiences. Educational institutions, including the University of Sydney and Berkeley Law, have adopted the series as a curriculum resource.
Following a production hiatus in late 2024, the podcast resumed in June 2025. The relaunch introduced a new monthly format, The 99% Invisible Breakdown: The Constitution, which features guest commentators analyzing the text of the Constitution chronologically.
Episodes typically focus on making complex legal concepts, such as the Emoluments Clauses or impeachment, accessible to a general audience. The show features theme music by the hip-hop collective Doomtree and has been highlighted by critics for its educational approach to constitutional scholarship.
Initially part of the Radiotopia network, the podcast was included in SiriusXM's 2021 acquisition of Mars’s production company, 99% Invisible Inc. Following a hiatus, Mars and Joh revived the show in June 2025 as a weekly production alongside a companion series, The 99% Invisible Breakdown: The Constitution, which provides a clause-by-clause analysis of the constitutional text.