The document discusses the voluntary carbon market, including its key features, products, standards, price trends, benefits and costs. It notes that the voluntary market includes renewable energy, forestry, and methane capture projects. Standards include the Gold Standard and Voluntary Carbon Standard. Price trends have declined from 2007 levels but top products remain steady. The market benefits less polluting industries but does not necessarily reduce emissions. Potential exists in Vietnam if projects are reliably validated, especially those combining renewable energy and social benefits.