Atlantoaxial dislocation (AAD), often caused by trauma, tumors or congenital malformations, is a challenging disorder of the craniocervical junction. Because of its deep location and intricate anatomic structure, the craniocervical junction is always a difficult region for spine surgery. With recent developments in medical science, great progress has been made in the diagnosis and treatment of AAD such that more instructive clinical classifications and efficacious treatment strategies, various novel operation techniques including innovative posterior or transoral anterior reduction, and novel fixation instruments are now widely used in clinical practice for managing AAD. However, surgeons continue to face more special characteristics and difficulty in carrying out upper cervical surgery than they encounter in other regions of the spine. Consequently, this high risk surgery should only be performed by extremely skilled and experienced surgeons and only when stringent indications have been met. Therefore, the aim of this course is to assist surgeons who are dealing with AAD by providing comprehensive information about AAD, including related anatomy, classification, clinical manifestations and diagnosis, imaging examinations and surgical techniques, thus decreasing the occurrence of complications and improving the level of diagnosis and treatment.