As with most joints in the body, MR imaging is highly effective at imaging the shoulder.? This issue reviews the use of MR imaging to rotator cuff disease and external impingement, Internal impingement syndromes, SLAP injuries and microinstability, and glenohumeral instability.? Also included in this issue are separate articles on technical update on MRI of the shoulder, novel anatomic concepts in MR imaging of the rotator cuff, and anatomic variants and pitfalls of the labrum, glenoid cartilage, and glenohumeral ligaments.? The issue also provides reviews of MR Imaging of the postoperative shoulder, MR imaging of the pediatric shoulder, and the throwing shoulder from the orthopedist's perspective.