The aim of this review article is to describe Programme for the International Assessment of Adult Competencies (PIAAC), summarize the basic findings and discuss possible implications for educational policy in the Czech Republic. We also discuss to what extent results from PIAAC complement empirical evidence from PISA, TIMSS and similar students’ assessments. We ask whether (and what) PIAAC reveals beyond these research projects. The article starts with a description of PIAAC methodology and it basic features. Second, we describe the results of the Czech population vis-à-vis other countries involved in the assessment. Third, we focus upon several core findings of PIAAC. In the final part we discuss implications of the findings for educational policy in the Czech Republic. PIAAC has confirmed several findings revealed in PISA and TIMSS, e.g. strong impact of socio-economic background upon students’ performance. Other findings, however, rather contradicted PISA and TIMSS. For instance, it was found that the results of Czechs aged 16–25 (which were under the international average in PISA and TIMSS) are above the average. PIAAC has been found to be unique and indispensable source of information, complementing students’ assessments. Although results in PISA and TIMSS are usually taken as a final and definitive indicator of the country’s stock of human capital, PIAAC has clearly demonstrated that at the age of 15 the competencies are far from definitely formed.