Green Key® is an international eco-label awarded to leisure organisations such as hotels, hostels and conference facilities. Green Key’s goal is to become the tourism industry's chief label based on numbers and demand. The Green Key label has been awarded to approximately 200 businesses in Denmark and about 4,000 businesses in 60 countries worldwide.

To obtain a Green Key label, the business has to meet a number of strict environmental requirements. In addition to environmental demands such as limiting the production of waste and decreasing the use of water and electricity, the criteria for the label also include certain requirements for policy, action plans, education and communication.