Hip arthroscopy has seen significant developments in the last 25 years. Until a decade ago, it was considered an emerging surgical technique, but today it is an established and effective treatment for various hip pathologies. The development of hip arthroscopy is strictly linked with the evolution of the concept of femoroacetabular impingement. The description of this new pathology and the open surgical treatment described by Professor Ganz were actually the basis for the development of hip arthroscopy. Femoroacetabular impingement is, nowadays, the main indication for hip arthroscopy. Femoroacetabular syndrome should be regarded as a triad of symptoms, clinical signs and imaging findings. The goal of the treatment, in these cases, should not be simple anatomic correction but to obtain a hip without impingement in the normal range of motion. In addition, labrum, cartilage, capsule and soft tissues should be evaluated and lesions should be treated. In particular, the role of the labrum has been investigated during the last several years and several techniques for labral repair and labral reconstruction have been developed. Despite the progress in diagnosis and treatment of several hip pathologies, the exact indications of hip arthroscopy are still debated. Defining the limits for arthroscopic treatment in cases of advanced osteoarthritis, bone deformity and periarticular soft tissues pathologies is one of the goals of current investigations concerning hip arthroscopy. This book is intended as a guide to the innovation and development in hip arthroscopy over the last 10 years ranging from an update of the surgical indications to rehabilitation after hip arthroscopy. In every chapter, an expert in hip arthroscopy discusses a specific subject focusing on latest trends and surgical techniques. Attention is focused especially on surgical indications, patient positioning and approaches, labral and capsular management, ischiofemoral impingement management, extra-articular pathologies, trauma and finally post-operative rehabilitation.