Many of the research results from the SACS and CO2STORE projects are published in the scientific literature but in a somewhat fragmented form. This report consolidates some of the key findings into a manual of observations and recommendations relevant to underground saline aquifer storage, aiming to provide technically robust guidelines for effective and safe storage of CO2 in a range of geological settings. This will set the scene for companies, regulatory authorities, nongovernmental organisations, and ultimately, the interested general public, in evaluating possible new CO2 storage projects in Europe and elsewhere. The report can be downloaded from http://nora.nerc.ac.uk/2959/.