Additionality
Proof that a carbon project reduces emissions beyond what would happen naturally in a business-as-usual scenario.
Additionality is a core concept in the carbon market. It ensures that the emission reductions achieved by a project are truly 'extra' and would not have occurred without the financial incentive provided by the sale of carbon credits. If a project would have happened anyway (e.g., because it was legally required or already financially viable), it is not considered additional.