60% of high school baseball pitchers suffer from debilitating arm injuries, and over half of them either don't return to baseball or have limited careers. This pervades all the way to professional baseball, where a quarter of the pitchers taking the mound have had surgery on their arms. Two factors are the major culprits - improper technique and muscle overexertion. The key is to get data on both factors, so that better informed and more comprehensive decisions can be made to preserve pitchers' arms.