Jonah Berger
Marketing professor at the Wharton School and author of Contagious. His most useful contribution to this site is not the book's framework but one finding inside the research behind it: interesting products get talked about immediately and no more than anything else thereafter, while products cued by the environment keep being talked about for months.
Who they are
Berger works on social influence, word of mouth and why things catch on, and he is unusual among popular authors in this area for publishing the primary research himself rather than retailing other people's.
Contagious (2013) sets out six drivers of transmission, of which social currency and triggers are the two this site uses. The book is readable and the research under it is real, and the chapter with the most evidence behind it is the one on triggers rather than the one on remarkability, which is the reverse of how the book is usually summarised.
He should not be confused with Joël Berger, a sociologist who appears elsewhere on this site for an unrelated replication, or with the Berger of the costly-signalling literature.
Key papers
Berger, J., & Schwartz, E. M. (2011). "What drives immediate and ongoing word of mouth?" Journal of Marketing Research, 48(5), 869-880. First author. More than 300 products, a multi-city field experiment and a laboratory study with real conversations.
Berger, J. (2013). Contagious: Why Things Catch On. Simon & Schuster.
Key ideas
The immediate and ongoing split. The finding that interesting products get a burst of word of mouth and no more of it over time, which the paper itself calls contrary to intuition, and which inverts the usual creative brief.
Triggers. Environmental cueing as the thing that sustains transmission. See Triggers.
Social currency. People share what makes them look good, which is well supported for the immediate effect and does not account for the long one. See Social Currency.
A caution we carry on his behalf: the outcome measured throughout is word of mouth and not purchase.
Sources
- Berger & Schwartz (2011), Journal of Marketing Research, verified at the published record 1 October 2026, doi:10.1509/jmkr.48.5.869.
- Contagious read in full in this vault, 2 September 2026, with reading notes.