Across social sectors, gamificaiton has emerged as an answer of first resort to a wide variety of grand challenges, from advocacy and fundraising, to education and training, to science and medicine, and beyond. But when is it the right strategy? Or the right tactic? In what instances have gamification and game mechanics been applied to produce successful, replicable outcomes? What about failures? Who really wins when games are deployed? Can we develop a common framework for evaluating opportunities for gamificaiton as a key element in addressing a complex problem? What are the success metrics we should be using? What data should we be using? See things from an insider's perspective: Case studies, data, and lesson's learned from leading game makers and their clients and partner organizations.