MRI currently offers the best imaging information for the diagnosis of subacromial pain syndrome, rotator cuff tears and osteoarthritis of the shoulder. The excellent anatomical and tissue specific imaging allows a detailed evaluation of the rotator cuff as well as the adjacent bony structures. If the cause of subacromial pain can not be determined despite extensive clinical, sonographical and radiological examination, MRI is indicated if there is a suspected pathology of the bony structures or the glenohumeral joint that could influence the further therapeutic procedures. In addition, MRI evaluation of muscular atrophy has become an important factor for determining appropriate therapy, particularly in cases of massive rotator cuff tears.