The objective of the EU SiteChar Project was to facilitate the implementation of CO2 geological storage in Europe by developing a methodology for the assessment of potential storage sites and the preparation of storage permit applications. Research was conducted through a strong collaboration of experienced industrial and academic research partners aiming to advance a portfolio of sites to a (near-) completed feasibility stage, ready for detailed front-end engineering and design and produce practical guidelines for site characterisation. SiteChar was a 3 year project supported by the European Commission under the 7th Framework Programme. This report introduces the lay reader to the research and concepts developed in the SiteChar project and can be downloaded from http://www.sitechar-co2.eu/SciPublicationsData.aspx?IdPublication=351&IdType=557.