Lack of a broader theoretical framework and a relative neglect of measurement issues have hindered many previous studies of age identity. In this paper, a case is made for viewing age identity as a dimension of self-concept and two measurement techniques are empirically compared. The first is a single-item measure in which the individual chooses the age category which best suits him. The second is a semantic differential procedure which involves rating the referents "An Old Person", "A Middle-Aged Person", and "Myself" on identical bipolar adjectives. Data were obtained from 341 men and women, age 47 to 96, residing in central North Carolina. The results support the validity of the semantic differential technique, and also suggest that the two measures tap somewhat different dimensions of age identity. The single-item measure is closely related to chronological age, while the semantic differential is more strongly related to personal and social correlates of aging.