A new method of estimating age at death from long bones for American Blacks and Whites. This paper demonstrates a new method for estimating age at death from long bones in American Blacks and Whites. The method uses the shape of the long bone to estimate the age at death and is applicable to both adult and immature skeletal remains. The method is founded on the idea that the morphology of the bones of a mature individual can change significantly while that of an immature skeleton remains relatively unchanged. The change is caused by secondary ossification centers developing in the epiphyseal cartilage. A detailed analysis of immature long bones shows that the development of the epiphyseal cartilage produces a predictable pattern in the long bone cross-sectional shape. Hence the shape of the long bone along with its cross-sectional area, length and weight can be used to predict the age of a mature individual. This morphological change of the long bone shape is modeled through the application of least squares regression and the resulting equation is used to estimate the age at death of Blacks and Whites. The regression equation can predict age at death within approximately +/-6 years for Blacks and +/-4 years for Whites. Since age at death is one of the most important components in assessing biological profile characteristics such as growth potential, it is important to have reliable methods for age estimation from long bones. The ability to predict the age of Blacks and Whites at the extremes of age (adult and juvenile) will contribute to the reliability of analyses that include age as a variable. The method could also be applied to estimate the age at death of immature skeletons. These estimates could be helpful in determining the sex of the immature skeleton and could also be important when forensic human remains are examined.