This paper investigates the role of human factors, in particular driving behaviour, in managing fleet fuel consumption. The results presented are from the Driving Simulator Eco-Drive Training (DSET) project, a collaborative project with a municipal fleet in Ontario, Canada, to test the effectiveness of simulator-based training in eco-driving techniques. Likert-scale questionnaires assessed the drivers’ self-reported motivation toward the training programme. In the six weeks following their simulator training session, we found that the average rate of hard acceleration (≥1.5 m/s²) among all acceleration events decreased from 13.3 to 11.4 % and the average rate of hard deceleration (≤−1.5 m/s²) decreased from 10.5 to 9.8 %. Based on these reductions in average acceleration and deceleration, approximately 18 % savings in fuel consumption is possible.