Public authorities spend 2 trillion Euros annually, which is equivalent to 19 % of the EU’s gross domestic product. They are big consumers who can influence the market in several ways. If public authorities decide to purchase products and services that are kinder to the environment they not only boost production of those goods directly but also influence the accessibility of those products and lower their price. Additionally, by purchasing green products and services public authorities provide incentives for businesses. Public authorities buy buses, tons of printing paper and millions litres of all kinds of cleaning products. The impact of the decision to buy more environmentally friendly versions of these products, can be huge.