What's holding up the Article 6 negotiations? Can differences be resolved at the 25th Conference of Parties (COP25) to the UN Framework Convention on Climate Change? This policy paper explains the crunch issues in Article 6 negotiations in generally accessible language. It sheds light on the key differences between negotiating Parties on the eve of COP25 in Madrid. Understanding the issues and Party positions is a key step to identify solutions in these highly political and technically complex negotiations.