In this article we review answers to 5 questions concerning the development of personality across the life course: How early in the life course can we identify characteristics unique to individuals that will show continuity over time? When in the life course is personality fully developed? What life course factors moderate continuity and change in personality? What are the mechanisms that promote continuity in personality? And finally, what are the mechanisms that promote change in personality? Based on the answers to these 5 questions we conclude (a) that there is modest continuity from childhood to adulthood, (b) that personality traits do not become fixed at a certain age in adulthood and retain the possibility of change even into old age, and (c) that with time and age people become more adept at interacting with their environment such that personality consistency increases with age and is more common than change in midlife and old age.