The next several years will be a key time for research that can enhance this evaluation and inform future policies to reduce GHG emissions and oil use from the light duty fleet. Major questions remain about consumer and manufacturer responses to the regulations and about how the costs and benefits of the rule should be estimated. Thus, for the research community, this evaluation is an important invitation to perform research that can aid the agencies in their deliberations. And, given the timeline, now is the time to start. Accordingly, RFF held a workshop with experts from academia, nonprofits, and industry, as well as from the key agencies and other government staff with responsibilities affecting the review to identify major research areas and projects that address key issues in the debate. Interested readers can learn about the proceedings, see the presentations made, and get a summary of the discussion at the workshop webpage.