Over the past 10 years, we have seen a tremendous explosion in the field of hip preservation and arthroscopic hip surgery. Traditionally, the evaluation and treatment of hip pain has been limited to traumatic fractures and arthritis, with few treatment options to offer athletes with hip injuries other than rest and rehabilitation for recurrent groin pulls, hip pointers, and bursitis. Building on the pioneering work of Reinhold Ganz and colleagues, we now recognize that symptomatic hip injury is directly related to the structural morphology of the hip and the unique mechanical loads applied to the joint by various activities. This work has helped us to appreciate that the diagnoses of recurrent “groin pulls” and hip pointers of the past may in fact reflect occult structural disorders of the hip in athletes. Femoroacetabular impingement (FAI) is now recognized as one of the most common causes of early chondral and labral injury in the nondysplastic hip. Abnormalities in the sphericity of the femoral head and offset of the head-neck junction are often seen in conjunction with focal or global acetabular deformity, resulting in repetitive mechanical collisions with terminal hip range of motion during athletic activities. The recognition and correction of these abnormalities in proximal femoral and acetabular morphology have offered great promise and excitement as possible interventions to significantly improve hip range of motion, address refractory groin pain in athletes, and potentially alter the natural history and progression of osteoarthritic changes. We now recognize that the implications of FAI extend far beyond the hip itself. Patients suffering from intra-articular hip injury associated with FAI often present with associated soft tissue compensatory injuries. The restricted terminal hip range of motion secondary to FAI creates abnormal mechanics and stresses both proximal and distal in the kinetic chain. We now recognize that spondylolysis, sacroiliac joint pain, adductor and rectus abdominus injuries, athletic pubalgia/sports hernias, and proximal hamstring injuries are more frequently observed in conjunction with FAI and may reflect the impact of abnormal hip mechanics on the proximal and distal kinetic chain. Similarly, recent biomechanical and clinical studies have shown an increased risk of anterior cruciate ligament injury in the knee in the setting of restricted internal rotation of the hip. The hip bone is indeed connected to the thigh bone! The growth in our understanding of FAI has been paralleled by a rapid advancement in our surgical techniques to address labral injury and osseous deformity in a minimally invasive fashion. Improvements in instrumentation and capsular management have vastly improved the visualization and access to treat osseous deformity and soft tissue injury via an arthroscopic approach. However, the learning curve is steep, and these new techniques have been accompanied by new challenges, including an increasing incidence of revision surgery for incomplete treatment of the deformity, iatrogenic chondral injury, and poor management of the labrum and soft tissues. Merging the comprehensive and thorough nature of a surgical dislocation of the hip with the minimally invasive approach of arthroscopy remains a critically important challenge in the years to come. In this issue of Sports Health, we present a series of articles that discusses not only what we know about pre-arthritic hip injury and the treatment of FAI but also what we do not know. Defining these voids in our understanding of the etiology, natural history, and treatment of FAI is both humbling and exciting and highlights the critical need for both translational and clinical research in the field of hip preservation. The quality and outcomes of our interventions can be considerably improved by further defining the ideal population that can benefit from our interventions. Understanding the etiology of the deformity may help to implement effective prevention strategies in the skeletally immature, athletic population. Long-term outcomes and randomized studies will be critical to truly define whether our surgical interventions for FAI not only offer short-term pain relief but also truly alter the natural history and progression of the osteoarthritic changes.