Three-dimensional (3D) preoperative planning has become the standard of care for the assessment and surgical management of anterior shoulder instability. Accurate quantification of glenoid and humeral bone loss is critical, as unrecognized osseous deficiency may lead to failure of soft-tissue repair. 3D computed tomography (CT) reconstruction remains the gold standard for evaluating glenoid morphology, bone loss, and the on/off track relationship of Hill-Sachs lesions, while also facilitating implant selection and trajectory planning for procedures such as the Latarjet. Recent advances in magnetic resonance imaging (MRI) allow isotropic 3D reformats that achieve comparable accuracy to CT, providing a radiation-free alternative for combined bone and soft-tissue evaluation. Beyond imaging, the application of new technologies, including 3D printing, navigation systems, and needle arthroscopy, is reshaping the diagnostic and therapeutic landscape of shoulder instability. Patient-specific 3D-printed models and implants enhance visualization and preoperative preparation. Navigation-assisted and robotic techniques offer the potential for more precise anchor placement, while needle arthroscopy introduces minimally invasive diagnostic and operative options. As technology continues to evolve, integrating 3D planning with advanced visualization and instrumentation promises improved patient-specific decision-making and optimized outcomes in shoulder instability surgery.