This document provides information about the OECD Programme for the International Assessment of Adult Competencies (PIAAC). PIAAC aims to assess and analyze adult skills and their impact. It will survey over 5000 adults aged 16-65 in over 20 countries to measure literacy, numeracy and problem-solving skills. The survey also collects background information to understand skill development and use. PIAAC seeks to help countries improve economic and social outcomes through better skills and their effective use.