Article 6 of the Paris Agreement on climate change outlines the basic rules under which countries signed up to the agreement can cooperate with each other to achieve their climate pledges, or Nationally Determined Contributions (NDCs).
An Article 6 carbon market will see countries able to transfer carbon credits earned through the reduction of greenhouse gases to other countries to help them meet their NDCs.
Article 6 has two main elements. Article 6.2 outlines the basis for countries to bilaterally trade 'Internationally Transferrable Mitigation Outcomes (ITMOS)' in a decentralised fashion. Article 6.4 is similar in design to the Kyoto Protocol's Clean Development Mechanism and will see companies and governments able to buy verified credits from a centralised pool. These credits will be accompanied by 'corresponding adjustments' to specify that the emissions reduction activity will not contribute to the host country's NDC.
While Article 6.2 has already seen trading activity, Article 6.4 has been delayed due to methodology disagreements.