Abstract The ligamentum teres (LT) has been studied since the 19th century, and its anatomy and biomechanical function have been well described. Recent advancements in hip arthroscopy have caused increased awareness of LT pathology. Previous reports have estimated the incidence of LT tears during hip arthroscopy to be 4% to 51%, and LT tears have been estimated to be the third most common reason for hip pain in athletes. Biomechanical studies have shown the LT's role in stability of the hip. Despite the growing body of literature on LT anatomy and function, its role as a causative factor in hip pain and hip instability has yet to be clearly defined, and the treatment of LT tears remains controversial. However, in certain cases where hip subluxation and overt instability are related to a traumatic full-thickness tear of the LT, reconstruction of the ligamentum has been suggested. We describe a technique for arthroscopic LT reconstruction using either a semitendinosus autograft or allograft in the supine position.