Carbon pricing very effectively encourages the shift of production and consumption choices towards low and zero carbon options that is required to limit climate change. Are countries using this tool to its full potential? This report measures the pricing of CO2-emissions from energy use in 44 OECD and G20 countries, covering around 80% of world emissions. The analysis takes a comprehensive view of carbon prices, including fuel excise taxes, carbon taxes and tradable emission permit prices. The "carbon pricing score" measures how close the 44 countries, together as well as individually, are to the goal of pricing all energy related carbon emissions at current and forward-looking benchmark values for carbon costs. The report highlights the structure of effective carbon rates across countries and sectors in 2018 and discusses change compared to 2012 and 2015. It also provides an outlook on recent trends in emissions trading in China and the European Union.