The perinatal mortality in Sweden is decreasing during the last 4 decades. From available vital statistics in 1976 Sweden''s figures are the lowest internationally. The decline continues and in 1978 the figure is as low as 10.0/106. The 5 yr period 1973-1977 is specially analyzed using medical birth records from all births. Data from an international perinatal study in 1973 coordinated by WHO are treated in the same way. With birth weight (BW) specific mortality rates in groups of 250 g late fetal deaths (LFD) are related to BW only for high BW and early neonatal deaths (END) are inversly related to BW. There is no sex difference in LFD but a marked male dominance in END, with 1/3 higher rate for the boys. BW specific mortality rates in BW groups of 250 g, separated in LFD and END, can be used as a tool for evaluating the quality of perinatal care. The influence of factors related to patterns and standards of living is emphasized. Perinatal mortality should be given in its 2 components separately, rates for LFD and END.