This report examines the impact shale gas drilling in the UK could have on water supplies, energy security and greenhouse gas emissions. The inquiry found no evidence that the hydraulic fracturing process involved in shale gas extraction - known as 'fracking' - poses a direct risk to underground water aquifers provided the drilling well is constructed properly. The MPs, nevertheless, urge the Department of Energy and Climate Change (DECC) to monitor drilling activity extremely closely in its early stages in order to assess its impact on air and water quality. Shale gas extraction could reduce the UK's dependence on imported gas, but it is unlikely to have a dramatic effect on domestic gas prices. The UK's onshore and, particularly, offshore shale gas resources could be substantial and the development of the offshore shale gas industry in the UK should be encouraged. Greenhouse gas emissions from gas are lower than from coal, but are still much higher than many low-carbon technologies. The presence of methane in shale gas, a greenhouse gas far more potent than carbon dioxide, has raised concerns. However, methane would only be released through leaks from the well or pipelines and the MPs are confident that this can be easily minimised through regulation and enforcement. Shale gas could reduce carbon dioxide emissions globally by encouraging a switch from coal to gas for electricity generation, but it will not be sufficient to meet long term emissions reductions targets and avoid the worst effects of global climate disruption.