To what degree is the course of human life prefigured by the childhood and adolescent years? John A. Clausen, long associated with the now famous Berkeley Longitudinal Studies, draws on sixty years of research from this, the largest long-term inquiry into human lives ever conducted, to answer this question. He demonstrates that "adolescent planful competence," a combination of self-confidence, dependability, and an investment in intellectual matters, has a significant and continuing influence on many aspects of our adult lives, even into old age. Over three hundred men and women born in the 1920s in California's Bay Area were studied intensively through their school years and periodically followed up since then by the Berkeley researchers. The study members lived through the Great Depression, several wars, and a sexual revolution.^ Although many developments in their lives could not have been foreseen, classifications made from data available for their adolescent years enabled Clausen and his colleagues to make impressive predictions of the paths their lives would take. Clausen shows how study members who, during their teenage years, displayed a high degree of planful competence made realistic choices early in life and were selected for promising opportunities as adults. Other aspects of personality, appearance, and social background also had long-term consequences, but adolescent planful competence proved far more potent than any other measure in indicating how lives would change, and who would experience essentially stable, as opposed to crisis-ridden, lives.^ By recounting in rich detail the stories of six relatively happy and successful study members, Clausen shows how adolescent competence was engendered and rewarded, and he illustrates in briefer, more disguised accounts the costs of mindless actions by the less competent. His research shows that personal crises were more frequent in every decade and had far more devastating and long-lasting impact on those who had shown little planful competence in adolescence. Clausen's data confirms that, despite potentially disruptive social pressures, adolescent planful competence will still be a potent predictor of achievement and satisfaction in adult life. This major study will be required reading for all people interested in human behavior.