Contagious: why things catch on book cover

Contagious

why things catch on

Jonah Berger
3.98 (32551 Reviews)

Overview of Contagious

Discover why ideas truly go viral in "Contagious" - the New York Times bestseller that challenges Malcolm Gladwell's theories with six scientifically-proven principles. Named 2014's Best Marketing Book, Berger reveals the surprising psychology behind what makes content irresistibly shareable.

Key Themes in Contagious

  • social transmission
  • word of mouth
  • viral marketing
  • social currency
  • consumer behavior

Quotes from Contagious

  • Social currency is about what we share says about us.

  • Making things more observable makes them easier to imitate.

  • If something is built to show, it’s built to grow.

  • When we care, we share.

  • Word of mouth is also precisely targeted.

Characters in Contagious

  • Jonah BergerWharton marketing professor and author

About the Author

About the Author of Contagious

Jonah Berger is the bestselling author of Contagious: Why Things Catch On and a leading expert in consumer behavior, social influence, and viral marketing.

A marketing professor at the Wharton School of the University of Pennsylvania, Berger holds a PhD from Stanford University and has spent over a decade researching the psychology behind why people share ideas, products, and content.

His influential works, including Invisible Influence: The Hidden Forces That Shape Behavior and The Catalyst: How to Change Anyone’s Mind, explore related themes of decision-making and behavioral change.

Berger’s insights have been featured in The New York Times, Wall Street Journal, and Harvard Business Review, and he advises organizations like Apple, Google, and Nike on driving cultural and organizational change.

Published in 2013, Contagious became an instant New York Times bestseller and has been translated into over 35 languages. Its framework for creating shareable content is widely taught in business schools and applied by marketers worldwide.

Download Summary of Contagious

Get the Contagious summary as a free PDF or EPUB. Print it or read offline anytime.

FAQs About This Book

Contagious by Jonah Berger explores why certain ideas, products, or behaviors go viral. It identifies six psychological principles (STEPPS)—Social Currency, Triggers, Emotion, Public, Practical Value, and Stories—that drive word-of-mouth transmission. Through case studies like the viral Blendtec blender videos and anti-drug PSAs, Berger reveals how to craft contagious content for marketing, social causes, or political campaigns.

Marketers, entrepreneurs, and business leaders seeking to amplify brand awareness will benefit from Berger’s research-backed strategies. Nonprofits, policymakers, and content creators can also apply its principles to drive social change or viral campaigns. The book suits anyone interested in behavioral psychology, viral trends, or practical frameworks for social influence.

Berger’s STEPPS framework includes:

  • Social Currency: Sharing makes people look good (e.g., exclusive clubs).
  • Triggers: Everyday cues that keep ideas top-of-mind (e.g., Kit Kat’s link to coffee).
  • Emotion: High-arousal feelings (awe, anger) drive sharing.
  • Public: Observable behaviors encourage imitation (e.g., Apple’s white earbuds).
  • Practical Value: Useful information gets shared (e.g., life hacks).
  • Stories: Narratives embed messages (e.g., Subway’s Jared campaign).

While Malcolm Gladwell’s The Tipping Point focuses on influencers and context, Berger emphasizes psychological drivers like emotion and practicality. Contagious provides a structured framework (STEPPS) for engineering virality, whereas Gladwell explores broader societal factors. Both books complement each other in understanding social epidemics.

Notable quotes include:

  • “Top of mind leads to tip of tongue”
  • “When we care, we share”
  • “People don’t just share information, they tell stories”

These emphasize the role of triggers, emotion, and narrative in viral content.

  • Leverage Social Currency: Create exclusivity (e.g., loyalty programs).
  • Use Triggers: Link products to daily routines (e.g., Kit Kat + coffee).
  • Craft Stories: Embed brand messages in relatable narratives (e.g., customer success stories).
  • Highlight Practical Value: Share data-driven tips or discounts.

  • Blendtec’s “Will It Blend?”: A blender destroying phones went viral, boosting sales.
  • Cheesesteak at Barclays Prime: A luxury restaurant’s $100 cheesesteak generated buzz.
  • Anti-Drug PSAs: Some campaigns unintentionally increased teen curiosity.

Yes. Berger draws from decade-long studies, including analyses of New York Times articles, product reviews, and social media trends. His Wharton School research on word-of-mouth transmission forms the book’s foundation.

Some argue the STEPPS framework oversimplifies virality, neglecting cultural or technological context. Others note limited guidance on sustaining long-term engagement post-virality. However, the book remains a benchmark for actionable marketing strategies.

With 72% of consumers trusting peer recommendations over ads, Berger’s principles help brands navigate social media algorithms and short-form video trends. Strategies like emotion-driven TikTok campaigns or LinkedIn thought-leadership stories align with STEPPS.

Shortform and Readingraphics offer concise summaries with infographics and audio versions. Berger’s website (jonahberger.com) also provides supplemental resources, including case studies and speaking engagements.

  • Made to Stick by Chip Heath: Creating memorable ideas.
  • Hooked by Nir Eyal: Building habit-forming products.
  • Influence by Robert Cialdini: Psychology of persuasion.

Explore Your Way of Learning

Contagious isn't just a book — it's a masterclass in Psychology. To help you absorb its lessons in the way that works best for you, we offer five unique learning modes. Whether you're a deep thinker, a fast learner, or a story lover, there's a mode designed to fit your style.

Quick Summary Mode

Read or listen to Contagious Summary in 9 Minutes

Break down key ideas from Contagious into bite-sized takeaways to understand how innovative teams create, collaborate, and grow.

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Contagious Lessons Told Through 24-Min Stories

Experience Contagious through vivid storytelling that turns innovation lessons into moments you'll remember and apply.

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