Business Case Studies & Business Publications

The Psychology of Influencers

Hagerty, Serena;Go...

Technical Note

The Psychology of Influencers

Hagerty, Serena; Goldblatt, Allison

M-1082 | Published June 3, 2026 | 7 Pages Technical Note

Collection: Darden School of Business

Product Details

As consumers distance themselves from traditional forms of marketing, brands are increasingly trying to reach them through social media influencers. The shift is significant: The influencer marketing industry tripled in market size between 2020 and 2025, ending the year at approximately $33 billion in value. What makes influencers so persuasive and effective? Six key psychological factors differentiate social media influencers from traditional marketing or advertising strategies: source credibility, social proof, persuasion knowledge, identification theory, parasocial relationships, and authenticity. In practice, these factors often blend with and reinforce each other, but examining each individually helps clarify why influencers are so effective. This technical note defines each of these psychological concepts, explains how influencers uniquely leverage it, and examines how social media platforms amplify its effectiveness. At the University of Virginia Darden School of Business, this note is taught in the first-year course "Digital Marketing" and the second-year course "Marketing and Society"; it would also be suitable in a module covering consumer behavior.