Extending application of Svalastoga's (1965) concept of system permeability to the intrasystem analysis of sex-race differentials in educational permeability in the rural South, an operational procedure was developed to quantify permeability as the percent variation in filial attainment of a status not associated with variations in parental status. Reviewing parental-filial correlations for educational status reported from: (1) The Occupational Change in a Generation Survey; (2) The Project Talent Panel; (3) The follow-up to the Explorations in Equality of Opportunity; (4) The Wisconsin Panel; and (5) The Southern Youth Study (S-81); data were analyzed and produced some tentative conclusions. Among these were: (1) comparison of black and white rates of permeability revealed that blacks' intergenerational competition for educational status was of a more egalitarian nature than similar white processes; (2) white males' educational permeability was greater than that for females; (3) based on Southern Youth data (354 white and 234 black males; 231 white and 207 black females), blacks were less likely to have aspirations for education corresponding to those of their parents' statuses and were less likely to translate their educational aspirations to actual attainment; (4) social origins influence achievement attitudes and attitudes influence attainment. (JC)