The distribution of family incomes is now slightly more equal than the distribution of husbands' earnings. Movements toward equal opportunity for women are likely to have only a small effect on family income inequality. In a world with no differences by sex in work behavior, we could expect that the work experience of women and men and the inequality in the distributions of women's earnings and men's earnings would be equal. The most unequal situation for family incomes in such a world would occur if the earnings of husbands and wives were perfectly correlated. Then, the degree of family income inequality would equal the degree of inequality in husbands' earnings (which would be the same as wives' earnings). Thus, in the long run, the women's movement and attempts to equalize opportunity by sex imply only a slight increase in the current degree of inequality even if husbands' and wives' earnings were to become perfectly correlated; under more realistic assumptions it appears that the economic advances of wives will not increase family income inequality. (Author/WI)