Posterior instability in athletes is a diagnostic and therapeutic challenge. Athletes have recurrent posterior subluxations rather than true dislocations, and they have pain rather than instability, which makes the diagnosis difficult. The pathology is usually capsular laxity rather than a true reverse Bankart lesion. There is not one diagnostic test, including computed tomography (CT) arthrogram, magnetic resonance imaging (MRI), or arthroscopy, that will always help with the diagnosis. Most athletes respond to conservative care with an exercise program designed to strengthen the posterior deltoid, the infraspinatus, and the teres minor; but, there is still a select group of athletes that cannot perform their sport after an extensive rehabilitation program. The surgical options for these athletes are varied, and the results in most cases are less than ideal. A posterior capsulorrhaphy was performed to treat this problem. This was initially performed with a staple, but this technique has been abandoned for a suture capsulorrhaphy to avoid staple problems. The 40 athletes treated operatively that had adequate follow-up evaluation reflected a 40% failure rate. Most of the failures were related to ligamentous laxity and unrecognized multidirectional instability not treated at the time of surgery. There may be subtle differences between a patient with posterior subluxation and multidirectional instability; these must be differentiated before operation. Also, the higher the competitive level of athlete, the worse the overall results. The high-level athlete must be informed that even if his or her shoulder is stabilized, the functional results may not allow him or her to continue at the same competitive level.