On July 20, 2006, in New York City, Resources for the Future convened a workshop of stakeholders and state officials engaged in the Regional Greenhouse Gas Initiative (RGGI) together with experts on various aspects of using auctions. The workshop provided technical assistance to states for the development of a plan to satisfy the requirement for an allocation of emissions allowances to benefit consumers or for strategic energy purposes. The workshop included an overview of auction theory, a panel on concerns of stakeholders about using an allowance auction in the RGGI, a panel on the motivations for and lessons from using auctions in other applications, and one on past experiences with auctions of emissions allowances. This workshop summary presents the main ideas presented by speakers and the audience. The summary concludes by drawing on the discussion to compile a suggested roadmap identifying steps for planners in moving toward implementation of the auction.