Atraumatic hip instability is an increasingly recognized source of pain and hip dysfunction. It can result from numerous causes, including femoroacetabular impingement, prior trauma, injury to the capsuloligamentous structures, and idiopathic etiologies. Occult hip instability can be a challenging diagnosis that requires careful attention to, and interpretation of, history, physical examination, and radiographic imaging findings. Iatrogenic hip instability is a potential complication of both open and arthroscopic hip-preserving surgical procedures that can have catastrophic results. Atraumatic hip instability is a pathologic entity that can be successfully addressed with open and arthroscopic procedures.