The United Nations strongly advocates for the role of sport in sustainable development. Specifically, the UN Framework Convention on Climate Change (UNFCCC) has established a framework called “Sports for Climate Action” with the aim of inspiring and motivating all sports organizations to actively contribute to global climate action goals.

The concept of sustainable development was defined in the report “Our Common future” (UN World Commission on Environment and Development, 1987) as “Development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. The concept is based on three fundamental pillars: environmental, social and economic.

In the context of outdoor events, the three pillars can be defined as follows:

Environmental pillar

Refers to the commitment to protect the environment by reducing the risks and measuring environmental impact.

Economic pillar

Refers to the economic development and growth of the local communities by preserving their environment and social rights.

Social pillar

Refers to the promotion of respect for individual rights and equality, as well as combating social exclusion and discrimination, promoting solidarity and contributing to the well-being of the local community where the event is celebrated.

The question of sustainability of outdoor events has been a topic of interest in the last years. Reducing the impact of any event requires to rethink the way most aspects of the event are organised: transport, supply, hosting… Decisions made by the event organisers are key to improve its sustainability.

In line with the sustainability principles that recognize the interconnections between socio-cultural, economic, and environmental systems, sport events also generate knock-on benefits. These events are the window to best practices in which the participants and public could reflect and learn from.

The Green Trail Concept online certification tool incorporates the 3 pillars of sustainability to provide trail running race organizers with a complete evaluation of the sustainability of their event. The categories considered in each pillar have been identified as the most important aspects of sustainability to focus on for race organizers and respond to an analysis based on the 7 principles of Leave No Trace Centre of Outdoor Ethics, theRegenerative EventsChecklist by Global Destination Sustainability Movement, the Checklist for Inclusive Events of Association Meetings International and Intellectual Capitals, the Indicators for Evaluation of Transparency by La Coordinadora de Organizaciones para el Desarrollo,the EU Corporate sustainability and responsibility guidelinesand the nature-based solutionsprincipal from International Union for Conservation of Nature (IUCN), among others.