It is widely maintained that to prevent catastrophic climate change from occurring, developed countries must reduce their emissions by 80 per cent relative to 1990 levels. In Canada, greenhouse gas emissions levels are increasing. Much of the growth has resulted from the transportation sector, with road transportation emissions accounting for the largest share. This report intends to provide an evidence-based view of the contribution that road transportation might practically make to achieving the "80 by 50" target in Canada. The report develops two cases that examine the potential emissions reductions that could result from a broad range of trends and technologies: a reference case and a continuous improvement case. The cases highlight that even with aggressive assumptions, Canada would still need to make significant adjustments to achieve the target.