Allegations about the scale and impact of political micro-targeting feed the news and shape the political agenda, including regulatory proposals at the EU level. In the world of online platforms, which make profit from targeted advertising, it seems inevitable that the popularity of this technique will grow. Since global internet platforms started to implement transparency tools, more data has become available for watchdog organizations and researchers to verify which practices actually take place. This session aims to inform policy debate on the use of political micro-targeting with evidence and data collected in Europe (e.g. in Poland during two consecutive election campaigns in 2019). We will discuss which risks posed by the use of this marketing technique exist in the European context and whether some form of regulatory response seems necessary.