Spinal deformities affect a considerable number of individuals of all ages. The etiological spectrum is broad and in cases of severe deformities a surgical treatment may be required. In addition to clinical evaluation, full spine radiographs constitute a fundamental tool, both in the diagnostic process as well as in the therapeutic follow-up of these patients. The aim of this paper is to provide a comprehensive overview on radiological assessment of spinal deformities, with an emphasis on scoliosis, by summarizing classical concepts and incorporating new ideas being developed in recent years, mainly due to the improvement and increased complexity of surgical management.