Partial-thickness tears of the rotator cuff are not rare and can be a cause of unexplained pain in the shoulder giving considerable disability. Although they occupy a significant position in the spectrum of disease of the rotator cuff, they have been inadequately defined and often elude diagnosis even by MRI and arthroscopy. In this review, the management of degenerative partial tears is considered. Those occurring in young overhead athletes resulting from repetitive microtraumata or internal impingement are included to allow their different causes to be recognized, which may necessitate specific treatment.