Over the past 20 years, the term agro-ecological zones methodology (AEZ) has become widely used for global regional and national assessments of agricultural potentials. The AEZ methodologies and procedures have recently been extended and newly implemented to make use of the latest digital geographical databases. At the same time a companion model of AEZ has been developed that enables assessments of potential productivity of forest tree species. AEZ follows an environmental approach; provides a standardized framework for the characterization of climate. soil and terrain conditions relevant to crop and forest species production; uses environmental matching procedures to identify limitations of prevailing climate, soil and terrain for assumed management objectives. The AEZ model includes an inventory of ecological adaptability characteristics as well as an inventory of specific ecological and environmental requirements for crop and forest tree species. The natural resources inventory is based on an up-to-date GIS database of climate, soil, terrain and vegetation covering China, Europe, Mongolia and the former Soviet Union. Results of potential productivity for miscanthus, willow and poplars in countries of Eastern Europe and Northern and Central Asia are presented for (i) all suitable areas, (ii) all suitable areas but excluding forests. urban areas and land that is potentially highly suitable for cereal production. The results show a large variation in potentials for bio-energy, in the various countries. In a few countries-Lithuania, Latvia, Romania, Georgia. Belarus and Azerbaijan, the potential for producing energy from miscanthus, poplar and willow alone is more than one-third of the cur-rent commercial energy use in these countries, even when forests and land potentially highly suitable for cereals are excluded from the assessment. (C) 2004 Elsevier Ltd. All rights reserved.