This book is the culmination of a five year research project exploring online gamers and the cultures they engage with, both virtually in the many massively multiplayer games and virtual worlds online, and in the physical spaces they inhabit in various play spaces around the world. The primary research questions concerned social learning in such spaces, i.e. how do players learn from one another what they need to be successful, and what are the associated norms and practices for doing so? What sorts of peripheral skills are gained, and are they applicable to physical world contexts? Finally, what does participation in such spaces mean for individuals who may have lacked other mechanisms for social learning, and what impacts might such findings have on existing educational structures?