“‘Smile Back’ was our contribution to Coca-Cola’s highly successful Where Will Happiness Strike Next? campaign. Grounded in the belief that something as simple as a smile can create a ripple effect of positivity, we sent people all over the world to smile at unsuspecting strangers to see if they would smile back. Unlike previous entries in the Happiness campaign, our idea had to be executable by regional Coca-Cola offices working autonomously. Not only did this idea pass muster with Coke employees—the approval decision was crowd-sourced among the entire global network—but also, it was implemented in multiple countries over the course of two years using our activation document as a guide.”