The application of newer imaging modalities such as ultrasound, CT, and MR imaging has made a major contribution to the understanding of pediatric hip disorders. Multiplanar imaging has been a major advancement in the depiction of the complex hip joint anatomy. Direct visualization of cartilage in the immature joint is now possible with MR imaging. Sophisticated computer software programs allow three-dimensional reconstruction of the joint from CT and MR data. Manipulation of three-dimensional images allows preoperative simulation of proposed surgical reorientation of hips with deformity resulting from dysplasia and Legg-Calvé-Perthes disease.