Not too long ago the best athlete was the one who played multiple sports and had all-around skills. But definitions of athletic excellence have changed over the years. An all-around athlete today is often pressured to specialize in one sport, or even in one position. This article suggests that sport specialization has emerged in connection with two changes in the larger society: (1) the privatization and commercialization of youth sports, and (2) the development of unique ideas about parenting, especially the definition of what constitutes a good parent.