Diploma and degree completion have become the fundamental standard for judging the performance of secondary and postsecondary educational institutions. Increasingly, leaders of education and workforce policy and programs assume that these measures of attainment effectively serve as indicators of adequate levels of essential literacy and numeracy skills. This report questions the soundness of such an assumption. A study by researchers from Drexel University's Center for Labor Markets and Policy and Educational Testing Service's Center for Research on Human Capital and Education finds that literacy skills of working adults are not as closely connected to levels of educational attainment as widely thought. Using Programme for the International Assessment of Adult Competencies (PIAAC) data on the literacy proficiencies of adults in the United States, the study finds that diploma and degree attainment is a less than satisfactory proxy for skills. These findings are important for policymakers and researchers. Relying on educational attainment as a measure of human capital (a proxy for skills) distorts understanding of the level of human capital that individuals and society in fact have. This raises critical questions about the desirability of public policies that focus on educational credentials without equal focus on the levels of skills associated with those credentials.