Several studies have shown that sex determination methods based on measurements of the skeleton are population specific. Metric traits of the long bones of the arm have been reported as reliable indicators of sex. In the current study, The material used consists of the arm bones of 204 adult individuals (111 males and 93 females) coming from the Modern Human Skeletal Collection of the University of Athens. The age range is 19-96 years for males and 20-99 years for females. The maximum lengths and epiphyseal widths were measured in the long bones of the arm (humerus, radius, and ulna). The discriminant analysis of the metrical data of each long bone gave very high discrimination accuracies. The rate of correct sex discrimination based on different long bones ranges from 90.30 percent (ulna) to 95.70 percent (humerus). In addition, intra- and inter-observer error tests were performed. These indicated that replication of measurements was satisfactory for the same observer over time and between observers. The results of this study show that metric characteristics of the arm bones can be used for the determination of sex in skeletal remains from Greece and that bone dimensions are population specific. (Published Abstract) Figure, tables, and references