While much interest is being shown for ‘climate neutral’ pledges by companies, and voluntary carbon markets, both can be confusing. This Policy Brief looks at the definitions and governance characteristics needed to deliver on both fronts. Successful markets need rules and oversight to function properly. Environmental integrity and robust carbon accounting lie at the heart of any markets that claim to benefit the environment. This Policy Brief sets out the building blocks of success, based on actual experience, and makes a number of recommendations on how to learn from the mistakes of the past