Millions of people play online games around the world, some for forty hours per week or more. Speculation abounds about both the positive and negative effects such a popular and time intensive activity might have on those who take part in it. In order to investigate how participation in these virtual worlds and the communities surrounding them might affect the player, three general research questions are posed. What factors contribute to players reporting that gaming has gone beyond being an engaging pass-time and begun to cause problems in their real life? Does play lead to social isolation or, instead, to an expansion in the social connectedness a player feels? Does involvement in online gaming lead to depression or can participation reduce depressive affect? Following a pilot survey involving 1836 respondents, a revised online survey was used to gather information from avid gamers about their gaming habits, attitudes, and feelings. Employing a longitudinal design, three waves of data were collected over a 14 month period from a sample including 2883 online gamers. Prospective analysis was used to establish causal and temporal linkages among the repeatedly measured factors. While the data provide some indication that a player's reasons for playing do influence the development of problematic usage, these effects are overshadowed by the central importance of self-regulation in managing both the timing and amount of play. An individual's level of self-regulatory activity is shown to be very important in allowing them to avoid negative outcomes like problematic use and, more broadly, depression. Further, the results indicate that participation in online gaming can lead to decreased isolation and enhanced social integration for those players who use online gaming as a medium in which to spend time and interact with real life friends and relatives. No causal link between online gaming and depression is observed, even in those individuals who report viewing their use as problematic. With responsible use, online gaming appears to be a healthy recreational activity that provides millions of people with hours of social entertainment and adaptive diversion. However, failure to manage play behavior can lead to feelings of dependency. Strategies and tools for addressing these self-regulatory deficits and supporting self-regulatory activity with respect to gaming behavior are discussed.