Objectives-The purpose of this study was to define and report on the effect of a comprehensive musculoskeletal sonography training program to improve accuracy (sensitivity and specificity) for the diagnosis of rotator cuff tears in relatively inexperienced operators. Methods-Before the training program was implemented, radiologists (n = 12) had a mean of 2 years (range, <1-12 years) of experience performing and interpreting musculoskeletal sonography. Pre- and post-training shoulder sonographic results were compared to surgical reports or, in their absence, to shoulder magnetic resonance imaging or computed tomographic arthrographic results if within 2 months of the sonographic examination. A total of 82 patients were included in the pre-training group (January 2010-December 2011), and SO patients were included in the post-training group (January 2012-June 2013). The accuracy, sensitivity, specificity, and positive and negative predictive values were determined for the presence or absence of supraspinatus and infraspinatus tendon tears. Results-After implementation of the training program, the sensitivity of sonography for detecting full-thickness rotator cuff tears increased by 14%, and the sensitivity for detecting partial-thickness rotator cuff tears increased by 3%. Conclusions-Quality improvement programs and acquisition standardization along with ongoing, focused case conferences for the entire care team increased the sensitivity of shoulder sonography for diagnosing both full- and partial-thickness rotator cuff tears, independent of the years of operator experience.