The objective of the TeleFOT EU project is to use large scale field tests to study the impacts of retro-fitted driver support services on traffic flow, traffic safety, the environment, mobility and drivers impressions of the service. The aim of this task, TeleBUS, is to study the impacts of the Green Driving Support device fitted into busses on traveling comfort, schedule keeping, and driving economy and to support user oriented development. The study group consisted of the Nobina drivers who were driving the Jokeri line busses fitted with Green Driving Support. The TeleBUS study compared the drivers using the Green Driving Support to the ones driving without one. The Klovi and Myllypuro bus depots of Nobina were also compared. The drivers opinions about the Green Driving Support device were studied using questionnaires and interviews. Passenger satisfaction data was gathered with questionnaires on the busses. The impacts of the device on fuel consumption, speed limit compliance and speed variations were studied separately for the entire line and for shorter study stretches. The main result of the study was that the use of Green Driving Support decreases fuel consumption and speeding. This impact can especially be seen during light traffic and on stretches where the driver can choose the speed i.e. the traffic environment or other traffic doesn’t affect driving. The passenger satisfaction questionnaire showed that passenger satisfaction during the morning rush hour and daytime varied significantly. In the morning respondents gave lower grades. These lower grades can be explained by rush hour traffic, concatenation of the busses and the passengers own hurry. The grades given by the passengers shows that in general, they are satisfied with the Jokeri line. The most important factor affecting traveling comfort was timetable keeping and real-time information about bus arrival at stops. The most important conclusion is that the use of Green Driving Support is worthwhile even years after training for both fuel consumption and speed limit compliance. Green Driving Support teaches to drive more economically also without the device but the difference to driving with the device is, however, clear. Speed behaviour of the trained drivers driving without Green Driving Support was similar to untrained drivers. The drivers should be regularly encouraged to use the Green Driving Support and economical driving should be kept as a part of driver training. Another conclusion is that the Green Driving Support device should be fitted to all vehicles and drivers should be encouraged to use it and to drive accordingly. According to the drivers this would decrease the stress related to driving and timetables. The benefits of the device would also be maximised. If trip quality is measured using passenger questionnaires, the time (rush vs. daytime traffic) and purpose of the trip should be taken into account when analysing the data.