The study focuses on the impact of the Energiewende (EW), i.e. German shift towards a decarbonized economy, and more specifically the large-scale deployment of renewable energy sources (RES), on the energy sectors of its eastern neighbors – the Czech Republic and Poland. Firstly, we provide a reflection of the EW by the Czech and Polish grid operators and energy policy decision-makers. Secondly, we introduce the possible pathways of EW’s future development, using the scenario analysis method. Thirdly, we provide a thorough explanation of the impact mechanisms through which the changes on the German electricity market are translated to changes to the ones of the Czech Republic and Poland. Fourthly, we evaluate the impact itself. Lastly, we provide a set of recommendations to both Czech and Polish decision-making bodies.