Background: Despite the successes of hip arthroscopy, clinical failures do occur, and identifying risk factors for failure may facilitate refinement of surgical indications and treatment. Knowledge regarding the reasons for treatment failures may also improve surgical decision making. Questions/purposes: We (1) characterized patients whose symptoms recurred after hip arthroscopy necessitating a revision hip preservation procedure or hip arthroplasty, (2) determined the etiologies of failure, (3) and reported the profile of revision surgical procedures. Methods: In a prospective database of 1724 consecutive hip surgeries, we identified 58 patients (60 hips) with a history of failed hip arthroscopy. Thirty-seven patients (38 hips) underwent revision hip preservation and 21 (22) hip arthroplasty. Thirty-nine (67%) were female. Demographics, etiology of failure, and type of revision surgery were analyzed. Results: Patients treated with revision hip preservation were younger, had a lower BMI, and lower Tönnis osteoarthritis grade at the time of revision surgery compared to patients treated with hip arthroplasty. Common etiologies of failure were residual femoroacetabular impingement (68%) and acetabular dysplasia (24%) in patients treated with revision hip preservation and advanced osteoarthritis in patients treated with hip arthroplasty. The revision preservation procedures included arthroscopy in 16 (42%), arthroscopy with limited open capsulorraphy in two (5.3%), periacetabular osteotomy in nine (24%), and surgical dislocation in 12 (32%). Conclusions: Residual or unaddressed structural deformity of the hip and underlying osteoarthritis are commonly associated with failure after hip arthroscopy. Thorough patient evaluation with detailed characterization of structural hip anatomy and articular cartilage integrity are critical to the selection of proper surgical intervention and successful patient outcome. Level of Evidence: Level IV, prognostic study. See Instructions for Authors for a complete description of levels of evidence.