Background From 2003, Helsinki knew that it was to host the 2005 World Athletics Championships, and realised that it needed an environment programme to support the event. Such mass events generate significant environmental stresses, particularly through the production of waste and the high transport needs of athletes, organisers and spectators. Both issues are major areas of environmental concern in Europe. The Helsinki University of Technology (TKK) is a known expert in environmental management and pro-environmental technology. It shared a commitment to efficiency, high-level technology and friendliness to the environment with the local organising committee for the championship. Together they created the first environmental programme in the history of the International Association of Athletics Federations (IAAF). They called the programme ECOmass, from “Eco-Efficient Major (or Mass) Event”. The programme looked to simultaneously reduce the environmental burden of the games and cut costs by promoting green energy, reduced CO2 emissions and waste management strategies. The procedures and the estimation of the effects of the environmental programme concentrated on traffic, waste disposal, communication, education, temporary building and energy efficiency. Objectives The project aimed to develop a best practice methodology and model for improved management of environmental performance at mass events, in particular sporting events. Based on the Eco-Management and Audit Scheme (EMAS) and in cooperation with local authorities, the project aimed to create and implement an Eco-Efficient Major Event Manual (EEMEM). The Manual was planned to consist of an Environmental Management System (EMS) framework, eco-efficiency criteria and a CO2 emission management module. A web-based tool and user guide for calculating emissions and coefficients would be produced. This would incorporate CO2 emission reduction into the environment performance assessments of mass events. The project aimed to test the model during the World Athletics Championships in 2005 and make the resulting manual available to mass events’ organisers in the EU and accession countries, as well as to the IAAF and its members. Results The most significant output of the ECOmass project was the Eco-Efficient Major Event Manual (EEMEM), which it compiled, tested and validated. The Manual is based on EMAS, however the strength of the project lies in its innovative adaptation of EMAS to cover the priorities of mass event organisation and elements like Life Cycle Analysis. It is not a direct EMAS handbook but a practical guide for event management from preparation to the analysis of results. Based on the systematic collection of data at the Helsinki Games, the Manual helps event organisers to reduce CO2 emissions, adopt life-cycle approaches and increase their general environmental awareness. Its strength is that the criteria and evaluation are transferable to the organisation of a wide variety of events and leisure activities in general, which is a growing sector of increasing environmental importance. 500 copies of the manual were distributed in English and French to Finnish, European and international organisations. These have included organisers of major events, future host cities, membership organisations of the IAAF and other organisers of major events, who are interested in the management of environmental effects. The Finnish Ministry of Education has agreed to support a new print of the Manual since the end of the project. The project successfully developed a web-based ‘climate calculator’ with an integrated user’s guide. This CO2 management module has proved useful in reducing CO2 emissions including in the beneficiaries’ offices. WWF Finland - which still maintains this free-to-use web tool - has adopted it as part of its Green Office campaign and such uses guarantee the sustainability of this tool, which can be easily used by organisations in different countries. The project completed an educational programme, including a wide range of stakeholders and cooperation partners, but mainly the volunteers (3,500) helping with the organisation of the World Athletics Championship. The intranet was used to create and uphold the e-learning platform, tested in the training sessions and workshops. The results and feedback were incorporated into the Manual. The results of the project were verified by an independent technical auditor and have been accepted by the IAAF, which will promote them to all its member countries. The project has also prompted the IAAF to start cooperation with the UN Environment Programme (UNEP) leading to a Memorandum of Understanding covering: sports and the environment; sustainable production and consumption patterns; and education and training. There was noticeable coverage of the project and its implementation in the Finnish national media. Outputs of the project included the manual, a Layman’s report and a TKK-produced brochure ‘Citius, Altius, Prudentius’.