Bone defects in posterior shoulder instability frequently occur with traumatic dislocations, and include postero-inferior glenoid bone loss and antero-medial humeral head bone loss (reverse Hill-Sachs lesions). It can also result from dysplasia, which is a spectrum of developmental malformation of bone and soft tissue, frequently presenting with postero-inferior glenoid deficiency, excessive glenoid retroversion and hypertrophy of posterior glenoid labrum and cartilage. A more recently identified risk factor for posterior shoulder instability is a flat and high-riding acromion providing less restraint against posterior humeral head translation. Quantifying posterior glenoid bone loss is critical and needs to be acknowledged preoperatively as the failure rates following soft-tissue-based reconstruction techniques increase significantly and in a similar pattern as observed in those with anterior shoulder instability. With the advancement of imaging-based measurement techniques accompanying reverse Hill-Sachs lesion can be calculated whether there is an ongoing risk of engagement. While there are known cut-off values of traumatic glenoid or humeral sided bone loss, in the setting of posterior shoulder instability associated with glenoid dysplasia, such cut-off values are yet to be established but usually focus on the extent of glenoid retroversion, postero-inferior glenoid bony deficiency and labral pathology in atraumatic cases and on whether glenoid-sided and humeral-sided bone defects are engaging in traumatic posterior instability. Posterior acromial pathology can be assessed on plain X-rays and include measurement of acromial height as well as more horizontal or vertical acromial orientation in the sagittal plane. The aim of all surgical procedures is to prevent engagement of bone loss, ongoing instability, pain and secondary osteoarthritis. The standard methods of arthroscopic posterior soft tissue reconstruction are still the most common and play a role in both traumatic labral injury and glenoid dysplasia. Restoring large posterior glenoid bone loss usually requires bone block procedures, which can be done open or arthroscopic-assisted. Humeral sided bone defects (reverse Hill Sachs lesion) can be filled with soft tissue (reverse remplissage-type procedure), or filled with a structural bone graft (auto- or allograft). A commonly overlooked (concomitant) pathology in posterior shoulder instability is excessive glenoid retroversion, and both posterior labral repair and isolated bone block procedures cannot address this bony abnormality. Correcting excessive glenoid retroversion can be done by opening-wedge osteotomy with local or distant bone graft, or by a procedure that combines a posterior opening-wedge osteotomy with combined glenoid concavity reconstruction using an implant-free, J-shaped iliac crest bone graft to address excessive glenoid retroversion as well as postero-inferior glenoid bony deficiency.