The member countries of the European Union plan to reduce their CO2 emissions in accordance with the international protocol agreed in Kyoto in 1997. The accepted options for doing this include fuel switching, improving energy efficiency, and the introduction of renewable energy sources. Geological storage of CO2 from fossil fuel use is also an option to reduce CO2 emissions, which does not require major changes in the energy infrastructure. Two projects are now under way in the European Union to study the potential for geological CO2 storage. The first project, known as GESTCO, will assess the potential CO2 storage capacity of the main sedimentary basins within Europe. GESTCO will examine in detail the geological storage potential and coincidence of CO2 emission sources to storage sites. In the North Sea the world’s first commercial geological storage project has now been in operation for 3 years. The natural gas from the Sleipner West field contains about 9% CO2, which must be reduced to 2.5% before sale. The CO2 is stripped by an amine scrubbing plant and then injected into a deep saline reservoir about 800 m below the seabed. To date, about 3 million tonnes of CO2 have been injected. To monitor the storage of CO2 in the reservoir, a project entitled Saline Aquifer CO2 Storage commenced in April 1998.