This report examines the economics of transporting and processing Alberta tar sands crudes in Quebec. In particular, we focus on the benefits and costs to Quebec of these activities, and address the widespread uncertainty and disagreement as to how Quebec could be affected by crudes from the tar sands. Tar sands proponents claim that Quebec will benefit from transport and processing of tar sands crudes, notably in terms of lower fuel (gasoline) prices and economic development (jobs and other spinoffs). In fact, more involvement in the tar sands would provide few (if any) benefits for Quebec, but would expose Quebec to substantial risks, costs, and negative environmental impacts. The report responds to the claims being made by tar sands proponents and explains why Quebec will not receive any significant benefits from more involvement with tar sands crudes, but will bear almost all of the risk/cost of spills and other environmental impacts. Conversely, tar sands proponents, will receive almost all of the benefits and bear little, if any, environmental risk/cost.