The diagnosis and treatment of elbow instability can be challenging for surgeons. Although history, physical examination, radiographs, and advanced imaging such as stress ultrasound scanning and magnetic resonance imaging are helpful, diagnostic arthroscopy is a valuable tool in the armamentarium of an elbow surgeon. Elbow arthroscopy is not only a diagnostic tool but also has the added therapeutic benefits that are not available with other diagnostic modalities. The purpose of this article and associated video is to present 3 arthroscopic techniques to help elbow surgeons arthroscopically recognize and quantify medial and lateral elbow instability.