Contagious

The science behind why some ideas spread and others do not. Jonah Berger, a marketing professor at Wharton, spent years studying what makes content go viral, products get recommended, and ideas stick in people’s minds. Contagious distills that research into six principles that explain why things catch on.

Why Start Here

Berger’s six principles, which he calls STEPPS (Social Currency, Triggers, Emotion, Public, Practical Value, Stories), give you a framework for thinking about word-of-mouth marketing. Each principle is backed by academic research but explained through engaging stories. You learn why some restaurants become the talk of the town, why certain YouTube videos get millions of views, and why some products practically sell themselves.

What sets this book apart from other marketing books is its scientific foundation. Berger does not rely on anecdotes or gut feelings. He draws on controlled experiments and data analysis to show what actually drives sharing behavior. The result is a set of principles you can deliberately apply to your own marketing, whether you are naming a product, designing a campaign, or crafting a social media post.

If This Is Marketing teaches you who to serve and Building a StoryBrand teaches you how to communicate, Contagious teaches you how to make your message spread. It is the perfect complement to the other two books in this guide.

What to Expect

A fast, engaging read at 244 pages. Berger writes with the clarity you would expect from someone who teaches complex ideas for a living. Each chapter focuses on one of the six STEPPS principles, with research findings woven into memorable stories. The book is accessible to anyone, regardless of marketing experience. You will finish it with a clear mental checklist for evaluating whether your marketing has the ingredients to spread on its own.