This paper begins by providing foundational descriptions of the social media environment and viral marketing, including relevant examples from current public policy events. Then, proposed is a conceptual model of virality in social media, induced from analysis of successful viral marketing campaigns. The SPIN Framework suggests four key success factors for viral campaigns: spreadability, propagativity, integration and nexus. Finally, both theoretical and actionable implications for scholars and public policy makers alike are discussed. Copyright © 2012 John Wiley & Sons, Ltd.