Abstract
Children's personality traits have enduring effects that shape adult well-being. In particular, childhood conscientiousness influences core aspects of adult well-being: health, friendships, and mastery. Research is now examining the mechanisms by which early personality traits initiate and sustain particular life paths. These include mediating and moderating mechanisms that may operate during critical developmental periods or may build cumulatively over time. Future research would benefit from testing theoretically derived mechanisms for different traits and examining variables as they change over time, using both short- and long-term longitudinal designs over different life stages.