There is concern among sports medicine practitioners that the number of youth baseball pitchers with elbow injuries appears to be increasing. Research points to overuse as the principle risk factor. The risk of elbow pain in youth pitchers is correlated with the number of pitches thrown in a game and in a season. Adolescents who competitively pitch more than 85 pitches per game, more than 8 months out of a year, or with arm fatigue are several times more likely to require elbow surgery. Poor pitching mechanics also appear to contribute to injury risk. Existing research does not show a significant correlation between curveballs and injury. Adults should help youth pitchers avoid fatigue, overuse, and improper mechanics. If elbow pain develops,the youth pitcher should be evaluated by a sports medicine physician. © 2009 by the American College of Sports Medicine.