An appreciation of adolescent growth and development is essential to the understanding of problems faced by the adolescent athlete. Early adolescence (ages 10-15 years) can be characterized as the body period. Physical growth is genetically determined and can be influenced by disease, injury, and nutrition. Early maturers are subject to adult expectations which may lead to either failure or excessive acclaim. Middle adolescence (ages 15-18 years) is the sexuality period, with special emphasis on gender identity. Friendships are critical, and athletics can be a focal point for showing love and affection without social fear. Late adolescence (ages 18-22 years) is the separation period. Young people with athletic skills leave home to face greater athletic and academic pressure and competition in college. Adjustment to this final adolescent period is achieved through learning to lose as well as win with grace and dignity.