Acromioclavicular (AC) joint injury is a frequent diagnosis after an acute shoulder trauma – often found among athletes and people involved in contact sports.This injury occurs five times more frequently in men than in women, with the highest incidence in the 20- to 30-year-old age group. Patients usually complain of pain and tenderness over the shoulder, particularly over the AC joint.Depending on the degree of injury, the clavicle may become prominent on the injured site.The original classification was described by Rockwood and Green according to the injured ligament complex and degree and direction of clavicular displacement.Many surgical procedures have been described; among these are screws, plates, muscle transfer, ligamentoplasty procedures and ligament reconstruction using either autograft or allografts.With the advancement of shoulder arthroscopy, surgeons are much more capable of performing mini-open or arthroscopically-assisted procedures, allowing patients an earlier return to their daily living activities. However, the results of conventional open techniques are still comparable.The introduction of new arthroscopic equipment provides a great variety of surgical procedures, though every new technique has its own advantages and pitfalls. Currently there is no gold standard for the surgical treatment of any type of AC injury, though it should be remembered that whenever an arthroscopic technique is chosen, the surgeon’s expertise is likely to be the most significant factor affecting outcome.Cite this article: EFORT Open Rev 2018;3:426-433. DOI: 10.1302/2058-5241.3.170027