Big changes are in play in global carbon credit markets. They were first formally set up under the Kyoto Protocol as additional means for developed countries to meet their binding emissions targets while financing emissions reductions and sustainable development where it was cheaper – i.e., in developing countries. The Clean Development Mechanism (CDM), the most famous of the Kyoto mechanisms, was a trailblazing program to certify and sell emissions reduction credits, including to private sector buyers. It also interacted with several compliance mechanisms, like the EU Emissions Trading Scheme (ETS). The decades that followed saw a scale up and evolution of carbon pricing mechanisms and international climate governance. Among notable developments were the US departure from the Kyoto Protocol, the EU ETS no longer accepting CDM credits, and the rise of so-called voluntary carbon market (VCM). Underpinned by a plethora of independent crediting programs and methodologies, the latter evolved to meet the needs of entities wishing to finance voluntary climate action, often to make a claim about their emissions balance (e.g., offsetting, carbon neutrality, or net zero alignment).