Joint implementation is one of the flexible mechanisms of the Kyoto Protocol (KP), defined in Article 6 of the KP. The mechanism allows Annex B countries (countries with emission reduction or limitation commitments under the KP) to earn Emission Reduction Units (ERUs) equivalent to one tonne of CO₂ through emission reduction/removal projects in another Annex B country. The ERUs can be counted towards meeting the country’s respective KP target.