The strength of influence upon statural variation of: (1) the degree of urbanization of the locality of habitat, (2) family size, (3) paternal and (4) maternal educational status was analysed in three generations of 19-year-old Polish conscripts, examined in 1965, 1986 and 1995. Each of the above factors of an individual's social situation was described by a 4-level scale. Each factor was found to exert a highly significant residual effect on stature throughout the three decades considered, even after the effects of other correlated factors were partialled out by three-factor ANOVA. However, the stratifying force of each factor, as expressed by the dispersal of the level-specific main effects around the national mean, has been changing over time. For example, the growth-stunting effect of the condition of coming from a large sibship was dramatic in the 1965 cohort and considerably attenuated in 1986 but ceased to diminish thereafter. The growth-enhancing effect of the condition of being a large-city dweller, initially marked, has almost disappeared; but the growth-stunting effect of the condition of being a rural dweller has remained equally strong across all cohorts. These and other shifts in the relative importance of the social factors, as presumed determinants of family living standards, are described and some explanations attempted.