This paper assesses the role of literacy skills as an equalizer in both educational outcomes and educational opportunities. First, by linking two surveys of adult skills for 11 OECD countries (PIAAC - Survey of Adult Skills (conducted in mid-1990s) and IALS - International Adult Literacy Survey (conducted in 2011)), the relationship between performance (average literacy test scores) across countries and within-country skill inequality (dispersion in literacy test scores) is examined. Although Okun's style tradeoff could suggest that there is a tradeoff between efficiency and equality, in this analysis the opposite holds true. Countries with higher average literacy test scores have, at the same time, higher equality in literacy test scores. Second, the role of intergenerational educational mobility (one aspect of equality of opportunity) across countries on both average literacy scores and equality in literacy scores is estimated. There is a significant effect of parental educational levels on children's test scores in all countries, but there is a substantial cross-country variation in the size of the coefficients, which suggests that families play different roles in the transmission of educational skills across countries. Furthermore, this paper finds that an increase in average literacy scores (particularly, improvement in the literacy skills of the low-skilled adults) is positively associated with higher intergenerational educational mobility and higher equality of literacy test scores. Third, by decomposing differences in average literacy scores between the surveys, this paper finds that although increasing educational attainment was the primary driver behind the rise in average literacy scores, literacy scores for each educational age group declined in all countries, which may imply a decrease in educational efficiency. From a policy perspective, increases in access to education and rises in educational attainment alone (although extremely beneficial) are not enough. A focus on educational reform and better quality of education are required in order to improve educational efficiency. Additionally, family policies and an active welfare state may be necessary in order to tackle inequalities. / Series: INEQ Working Paper Series