The recent growth in unconventional natural gas production has also produced a profusion of publications on the exploration, development, production, infrastructure, economics, uses, and environmental impacts of these resources. This book summarises the current state of published descriptions of the potential environmental impacts of unconventional natural gas upstream operations within the Lower 48 United States. It also examines the technology, impacts and regulations of hydraulic fracturing, which is a key technique that has enabled the economic production of natural gas from shale deposits, or plays.