It seems obvious, for example, that a project should reduce emissions below the level that would have occurred without that project, a condition known as “additionality.” But that’s not always the case. Thanks to hazy interpretations of that proviso, “at least half” of current projects wouldn’t meet a uniformly strict assessment, says Michael Schlup, director of the Gold Standard Foundation in Basel, Switzerland, an organization dedicated to eradicating just such inconsistencies. His group unveiled what’s designed to be a rigorous, industry wide protocol in May, and says that around 20 projects are currently applying the code. A rival benchmark Voluntary Carbon Standard is expected to be drawn up soon by the International Emissions Trading Association and the U.K.’s Climate Group.