The ability to understand, evaluate, and use written information (literacy), process and communicate mathematical information (numeracy), and access and use digital technology are foundational to full participation in today's global, knowledge-based societies. This paper employs the 2012 Program for the International Assessment of Adult Competencies (PIAAC) that directly assessed the cognitive skills of adults ages 16 to 65 in 24 Organization for Economic Cooperation and Development (OECD) countries, including the United States. This report analyzes the U.S. data on English literacy and numeracy among U.S. immigrant adults and explores how their cognitive skills--skills that are tested in English--are related to key immigrant integration outcomes such as employment, income, access to training, and health. Overall, the PIAAC results indicate that U.S. adults fared worse than most of their counterparts across the participating countries in the tested areas of proficiency (i.e., literacy, numeracy, and problem solving in technology-rich environments). The results are significant because research finds that literacy and other cognitive skills are strong predictors of income, employment, education and health and because differences in skill levels are an important source of widening income inequality.