The assessment of fetal age at death is fraught with many complications and often the determination of the maturity of the fetus is a more realistic solution to the question of fetal viability. This study examines the pattern of appearance of primary centres of ossification in the fetal hand and foot, in an attempt to construct a maturity continuum. The results show that completion of ossification in the hand precedes that in the foot and generally occurs in a more regular pattern. The method proves useful at assessing fetal maturity between the third and tenth months of intra-uterine life. In addition, the relationship to other major centres of ossification is considered.