Assessment of sex from femoral dimensions has been tried before in several populations. Studies conducted so far have demonstrated that populations differ from one another in size and proportion. The discriminant formulae developed for determining sex for one population group cannot be applied on another. This study establishes standards for determining sex from complete femurs in a modern Bulgarian population. The sample is composed of 140 femora (82 male and 58 female) from adult individuals born after 1920. Twelve measurements were taken. No statistical difference was found between the right and left side (P > 0.05). The mean values of all measurements were significantly higher in males as compared to females (P < 0.001). The most dimorphic single parameter on the basis of univariate discriminant function analysis was linear dimension - maximum length of femur with 90.0 % accuracy rate for sexing individuals. The combination of maximum length, midshaft circumference and bicondylar breadth according to stepwise discriminant analysis provided the best result with 95.7% accuracy. These findings indicate that linear dimensions such as length are more discriminating than breadth and circumference measurements in long bones, unlike the previous studies. Probably this is due to the influence of specific genetic factors. On the other hand, the current forensic practice whereby criminals dismember the remains of their victims in an attempt to make their identification difficult requires that simple methods of sex determination from fragmented skeletal remains are available to forensic anthropologists and skeletal biologists. The head of the femur and the distal femur are an example of such bone fragments. Identification and demarking points have been derived from the maximum diameter of the head and the distal epiphyseal breadth of the femur and used to determine the sex of individuals. The objectives of the present study were therefore to establish the standard numerical values of the identification and demarking points for sex determination in Bulgaria. The maximum head diameter and the distal epiphyseal breadth identification point and demarking point were found to be sexually dimorphic. The numerical values of the male identification and demarking points were higher than the corresponding female values.