The Program for the International Assessment of Adult Competencies (PIAAC) is an international survey that measures adults' proficiency in key information-processing skills - literacy, numeracy, and problem solving in technology-rich environments. It is coordinated by the OECD and involved over 20 countries in its first round. PIAAC provides data on adults' skills and how they relate to social and economic outcomes. It assesses skills through background questionnaires and measures of literacy, numeracy, problem solving, and other domains. Results are reported by the OECD and participating countries to further understanding of adult skills and inform policy.