This report summarises information on exploration and production (E&P) activities carried out by contributing OGP member companies in 2011. Forty one member companies working in 75 countries worldwide have submitted data for the report. This total includes 5 companies reporting for the first time this year and all of the 36 companies that contributed data in 2010. Information is aggregated at both global and regional levels and is expressed within 6 environmental indicator categories: Gaseous emissions; Energy consumption; Flaring; Aaqueous discharges; Discharges of non-aqueous drilling fluids retained on cuttings; and Spills of oil and chemicals. These data represent oil and gas wellhead production of 2,221,462 thousand tonnes, about 32% of 2011 global production sales†. This is a 2% reduction in production compared to 2010. However, regional coverage is uneven, ranging from almost all known production in Europe to 9% in the Former Soviet Union (FSU).