Because of the relative importance of climate change and the legislative, cost, and supply chain governance factors driving attention to it, this study shall focus on the greenhouse gas emissions, specifically carbon dioxide (CO2), associated with logistics. While we include transportation activities, we focus on impacts due to lean practices rather than other improvements that have been made to make vehicles more fuel-efficient. Additionally, we shall focus on the supply chain link between a manufacturer and a retailer, although the hypotheses and findings can be generalized to any portion of the supply chain. We will use a discrete event simulation, modeled after a prototypical supply chain in North America, to test our hypotheses.