Background Transport contributes significantly to air pollution and greenhouse gas emissions, which must be drastically reduced in the near future in order to limit global warming. While mobility is also considered a vital social good, transport emissions need to be monitored and understood. Auto manufacturers are improving the efficiency of their vehicles, but these modifications alone are not enough. Complementary approaches are necessary, addressing the number of vehicles on the road and the related impacts (such as congestion that causes vehicles to stop and start) without dramatically limiting people’s mobility. The topographic characteristics of the city of Bolzano in the Italian province of South Tyrol facilitate the accumulation of air pollutants over the city under certain unfavourable meteorological conditions. These pollutants are produced by several emission sources (in particular traffic, domestic heating systems and factories) and can have negative impact on the urban environment as well on the health of local people. The most relevant concern relates to the high levels of nitrogen dioxide (NO2). In the past few years, the annual average has in fact exceeded the limit of 40 μg/m3 set by law. This pollutant is responsible for several illnesses of the respiratory system. It has been estimated that about 60% of NO2 emissions is caused by urban and highway traffic. Another important challenge relates to the need to reduce the local contribution of greenhouse gases emissions, in particular CO2. In this case, the contribution associated with freight and passenger transport is less significant but not negligible, and originally estimated in the order of 30%. In the past, most cities have tried to address such environmental problems with drastic and often unpopular solutions, such alternate number plate access or the prohibition of the circulation of motorised vehicles. The traditional approach has been to build new road infrastructures, which is typically very expensive and produces no immediate effects. Objectives The main objective of the INTEGREEN project was to demonstrate a system that will provide the public authorities in Bolzano with correlated traffic/environmental information on which they can base their eco-friendly traffic management policies. In order to achieve this aim, the INTEGREEN system would integrate dynamic traffic and environmental data provided by vehicles with static environmental data collected by the city's environmental network stations. In addition, on the basis of the validated INTEGREEN framework, the project would study and demonstrate the quantitative impact on the urban environment of specific traffic policies, including novel strategies. Results The INTEGREEN project addressed the issue of air pollution levels and the greenhouse gases emissions produced by urban traffic in the city of Bolzano. It developed a new system that is able to measure accurately both traffic and air pollution conditions in the city. Moreover, through automatic calculations, it is possible to gain a quantitative overview on a real-time basis. All available information (including data measured by official air quality stations managed by the Local Agency for the Environment of the Autonomous Province of Bolzano) was integrated into the system, which also introduced new innovative measurement mechanisms. In two streets with high levels of traffic of the city, two new air pollution measurement stations were installed and coupled with traffic detectors. These integrated stations allow for detailed correlation analysis of traffic and air pollution conditions. Also, an innovative system for the measurement of the vehicular travel times has been installed on the main streets of the city. It is a very low-cost system, based on the anonymous detection of the Bluetooth devices on board moving vehicles. Moreover, a system for the mobile measurement of traffic and air pollution on local roads was developed. Since October 2014 a prototype of this unit has been installed on one of the public transportation vehicles of the city bus company. In this way, it has been possible to collect a unique dataset for better understanding traffic and air pollution phenomena. All this data is collected and automatically recorded in a central database management system, which is accessible to technical staff of the Municipality of Bolzano through an interactive control panel. The different traffic and air pollution conditions can thus be evaluated and efficient measures can be introduced to prevent air pollution peaks caused by urban traffic. Through a detailed analysis of all the data that is available today, in particular that which is related to critical conditions brought about by bad weather or a high levels of visitors to the city, it has been possible to define the amount of emissions that can be reduced through proper traffic management strategies. More efficient management of traffic and mobility demand can reduce emissions by more than 30%. During the implementation of the project, tests of eco-friendly policies were carried out, and the INTEGREEN system was used to evaluate relevant environmental performance. The introduction of speed enforcement detectors has had a particularly beneficial impact that is greater immediately after their installation. Emission reduction was estimated in the order of 10%. Other tests, such as changing traffic light cycles and launching a new set of advanced informative services for local travellers, have had a less evident impact. These actions, however, have been shown to be very important in stabilising traffic conditions and lowering local air pollution peaks. In order to further promote sustainable mobility among local citizens, in particular during critical conditions, the project has produced two free Apps: BZBus, which gives real-time positions of city buses making them more convenient to use; and BZTraffic, which allows users to know in real-time the likely times for passing through key streets in the city. The apps also allow for comparisons to be made between current trends and those of the past along the travel times one could expect by bicycle. Such a comparison highlights the often lack of advantage of travelling by car in the city. A third App, BZParking, was launched in the scope of the complementary European Regional Development Fund co-funded project ‘Bolzano Traffic’. The App gives users an update on parking areas in the city. Finally, the project embarked on a collaborative process involving students to transform urban mobility and promote a culture of sustainability. The team promoted this message of ‘eco-driving’ – such as following the on-board advice on gear changing and cruise speeds common to new cars – at large-scale public events Overall, the project boosted the public’s understanding of the link between traffic and air pollution. New monitoring stations will only increase understanding of this link in the future and will allow new and more efficient measures to be developed – for example, dynamic changes to traffic light cycles, improved traveller information services, and better policies for the management of heavy transit vehicles through the city. The project also helps to implement the European Commission Communication, ‘A Clean Air Programme for Europe’ COM(2013) 918 final. The INTEGREEN system can potentially be easily replicated in other similar urban areas. In the last few years, many public administrations have started to introduce air pollution measurements for traffic management purposes. Tools and approaches developed in the project could enrich the local experiences which have already started. By working closely with local industry, it has been possible commercial applications and components that could support the deployment of similar systems have received a great push. The wide use of open source software solutions and cost-effective hardware devices offers the possibility to significantly reduce the barriers for the large-scale penetration of the various innovations carried out by INTEGREEN. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).