J.M. Berger is a writer and researcher focused on extremism as a Senior Research Fellow for the Center on Terrorism, Extremism, and Counterterrorism at the Middlebury Institute of International Studies. His research encompasses extremist and terrorist ideologies and propaganda, including social media and semantic analytical techniques. He is the author of four books, including Extremism (2018) and Optimal (2020). 

Berger is also a research fellow with VOX-Pol and a PhD candidate at Swansea University's School of Law, where he studies extremist ideologies. As a consultant for social media companies and government agencies, Berger conducts research and training on issues and policies related to homegrown terrorism, online extremism, advanced social media analysis, and countering violent extremism (CVE).  

Berger's most recent nonfiction book, Extremism (MIT Press, August 2018), was named an Outstanding Academic Title for 2019 and has been reviewed as "meticulous," "an excellent primer," "exceptional" and "elegantly written." 

His debut novel, Optimal (2020), is a dystopian tale about a world run by algorithms and social media. Reviewers have praised it as "gripping," "absorbing" and "great storytelling." A member of the Science Fiction and Fantasy Writers Association, Berger is currently working on his second novel, a fantasy epic grounded in his research on extremism.