Over half of the US supply of marine-derived crude oil now comes from wells deeper than 1500 meters (one statute mile) water depth – classified by industry and government regulators as “ultra-deep” production. A number of factors make ultra-deep exploration and production much more challenging than shallow-water plays, including strong ocean currents, extremely high pressures and low temperatures at the sea bottom, varied sub-bottom rock and sediment strata, and high oil and gas reservoir pressures/temperatures. All of these factors, combined with the extremely high production costs of ultra-deep wells, create enormous challenges to explore, develop, and produce from ultra-deep oil and gas extraction facilities safely and with minimal environmental damage. In the wake of the Deepwater Horizon and other well blowouts, a considerable body of scientific research on the fate of spilled oil and the resulting environmental effects of deep blowouts has emerged. This and a companion volume, published by Springer, Scenarios and Responses to Future Deep Oil Spills: Fighting the Next War, are intended to contribute to the ongoing and important task of synthesizing what we know now and identifying critical “known-unknowns” for future investigation. How can society minimize the risks and make informed choices about trade-offs in the advent of another ultra-deep blowout? Also, what research questions, experiments, and approaches remain to be undertaken which will aid in reducing risk of similar incidents and their ensuing impacts should ultra-deep blowouts reoccur? It is to these questions that this volume intended to contribute.