There are no readily available radiological criteria for evaluating the depth of the lordotic curve of the cervical spine in normal individuals. In this paper there will be presented a method for determining such measurements. The cervical spines of 180 white persons (90 men and 90 women) taken at random from a group presenting themselves for routine chest studies were examined radiologi-cally. None of these had any complaints referable to the neck nor was there any history of previous injury. The ages ranged from twenty-one to eighty years. Fifteen of each sex were studied in each age decade (Table I). A right lateral roentgenogram of the cervical spine was made at a distance of 6 feet with the subject in a neutral sitting position and looking directly forward at a marker fixed on the wall at eye level. The hard palate was parallel to the lower border of the roentgenogram and the angles of the mandibles were superimposed. All the examinations were made by the same technician using the same technic, thus ...