A method is presented for cross-country, cross-time comparison of energy efficiency developments in the manufacturing industry, The method is based on the use of physical production data as a measure of activity growth for the manufacturing industry, The methodology was applied to the pulp and paper industry of eight countries of the Organization for Economic Cooperation and Development (OECD), With the methodology it is possible to follow energy efficiency developments, separately, for fuel and electricity consumption. Between 1973 and 1991, the production growth in the pulp and paper industry in the analysed countries would have resulted in an average increase in the primary energy consumption by 42%, Changes in the product mix had hardly any effect on the primary energy consumption, Because of energy efficiency improvements, the growth of primary energy consumption was limited to only 16%, The average annual efficiency improvement amounted to 1.6%, The methodology presented enables physical energy efficiency comparisons to be made between countries without the need for data at the process level.