This companion volume to the first OECD Skills Outlook (OECD, 2013) offers an overview of the “what” and “how” of the Survey of Adult Skills, a product of the Programme for the International Assessment of Adult Competencies, or PIAAC. Its primary objective is to help readers to understand and interpret the results from the survey. To this end, it explains, in a non-technical way, the methodologies underpinning the design of the Survey of Adult Skills (PIAAC) and operational aspects of the survey, such as sampling, data collection and response rates, and how results are reported. A more detailed and technically oriented presentation of the survey, the methodologies used, and the quality of the data output can be found in the Technical Report of the Survey of Adult Skills (OECD, 2013, forthcoming).