Events have always played an important role in our society since they are a way to gather and share experiences on music,sport,culture,economy or even only for socialization.The number and variety of events has increased over the past years and the process of globalization has facilitated the constantly increasing participation at international level.As consequence,also the impact on climate change of events is constantly rising,as well as the awareness of citizens and participants on this topic,with the growing request to take action on the GHG(Greenhouse Gas)mitigation.It shall be noted that there is still lack of clarity on the most suitable quantification methodology which shall be used.The two main approaches are the CFP(Carbon Footprint of Product)and CFO(Carbon Footprint of Organization).The most suitable one seems to be the CFP since it is more able to describe an event intended as a service provided to the participants.An important consequence of this approach is the need to develop a PCR(Product Category Rule),with the purpose to establish common rules for the CFP quantification,in order to increase consistency in the methodology and comparability of the results with other events.This PCR was developed on the basis of the Hero Dolomites event case study,here described.The clarity on the most effective methodology for the carbon footprint quantification is fundamental for allowing the implementation of suitable GHG reduction plans by event’s organizers,considering the reliable quantification as the base for any GHG mitigation path,even in direction of credible carbon neutrality targets.