Two noted Japanese economists join forces with a Russian statistician to assess and analyze the size of Russia's oil and gas sector. The authors discuss the methodology favored by Goskomstat Rossii that is based on the System of National Accounts (SNA) and data supplied by enterprises, and introduce their alternative calculations to approximate the sector's share in the Country's GDP. Their method is based on a modification of input-output tables, utilizing enterprise groups as units of statistical observation. Both methods are then compared and the resulting discrepancy traced to the sector's specific characteristics rather than to faulty methodological treatment by Goskomstat Rossii.