This article reflects on European education policy which is driven by benchmarks and indicators. While the European benchmark on adult lifelong learning participation--15% to be achieved by 2020--is measured by the Labour Force Survey, the Eurostat Adult Education Survey (AES) was designed to better understand the topic of adult lifelong learning participation in-depth. This article explores the AES as an instrument to inform policy-makers and whether it provides adequate information to empirically testify participation hypotheses. The article argues that analysis of the AES provides limited understanding of the educational supply side. Furthermore, policy-makers should be aware of methodological and conceptual weaknesses before relying on these data in their policy development.