In 2009 at COP 15, decision 4/CP.15: "Methodological guidance for activities relating to reducing emissions from deforestation and forest degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries" provided more substantive information on requirements for REDD+. Specifically, the national forest monitoring system was introduced, with elements of measurement, reporting and verification (MRV). Countries were encouraged to develop national strategies, develop domestic capacity, establish reference levels, and establish a participatory approach with "full and effective engagement of indigenous peoples and local communities in (…) monitoring and reporting".