There is increasing recognition that achieving deep cuts to GHG emissions requires a close link between long-term strategic planning and short-term policy action. Thus, Article 4.19 of the Paris Climate Agreement called on countries to develop long-term low GHG emissions development strategies, and to present them by 2020. To implement this requirement across all 28 EU countries, the EU is in the process of agreeing guidelines and minimum requirements. This study highlights lessons that can be learned from recent experiences with 2050 decarbonization strategies in selected EU countries. It builds on these experiences to highlight some examples of good practice when it comes to long-term decarbonization strategy development. It also highlights implications of these experiences for the guidelines and requirements that are being drawn up by the EU.