This research assesses the impacts of developing shale gas in the UK, with the focus of determining whether or not it is possible to develop it sustainably and how it could affect the electricity and gas mix. There is much uncertainty on the impacts of developing shale gas in the UK, as the country is currently in the early stages of exploration drilling and the majority of studies which have been carried out to analyse the effects of shale gas development have been US specific. To address these questions, the environmental, economic and social sustainability have been assessed and the results integrated to evaluate the overall sustainability. The impacts of shale gas electricity have been assessed so that it can be compared with other electricity generation technologies (coal, nuclear, renewables etc.), to ascertain its impacts on the UK electricity mix. Life cycle assessment is used to evaluate the environmental sustainability of shale gas electricity (and other options), while life cycle costing and social sustainability assessment have been used to evaluate the economic and social sustainability. Multi-criteria decision analysis has been used to combine the results of three to evaluate the overall sustainability. The incorporation of shale gas into the UK electricity mix is modelled in two future scenarios for the year 2030. The scenarios compare different levels of shale gas penetration: low and high. The results show that shale gas will have little effect on improving the environmental sustainability and energy security of the UKâs electricity mix, but could help ease energy prices. In comparison with other options, shale gas is not a sustainable option, as it has higher environmental impacts than the non-fossil fuels and conventional gas and liquefied natural gas: 460 g CO2-Eq. is emitted from the shale gas electricity life cycle, while conventional gas emits 420 g CO2-Eq. and wind 12 g CO2-Eq. The power plant and drilling fluid are the main impact hot spots in the life cycle, while hydraulic fracturing contributes a small amount (5%). In addition to this, there are a number of social barriers which need to be addressed, notably: traffic volume and congestion could increase by up to 31%, public support is low and wastewater produced from hydraulic fracturing could put strain on wastewater treatment facilities. However, the results indicate that shale gas is economically viable, as the cost of electricity is cheaper than solar photovoltaic, biomass and hydroelectricity (9.59 p/kWh vs 16.90, 11.90 and 14.40 p/kWh, respectively). The results of this thesis show that there is a trade-off in the impacts, but because of its poor environmental and social ratings shale gas is not the best option for UK electricity. The results also identify areas for improvement which should be targeted, as well as policy recommendations for best practice and regulation if shale gas were to be developed in the UK.