After stressing the need for, and difficulties in, long-term supranational energy-supply strategies, the author describes a high and a low scenario. Both are fairly conservative, even in their assumptions on the main variant, economic growth. Quantified for seven world regions via a set of highly iterative models, the scenarios give a conceivable energy-demand range over the next 50 years. By 2030, nuclear power may supply over 20% of the world's energy; coal, in the form of synthetic fuels, will be replacing oil. Resource allocation and trade flows will in general be restricted by production ceilings. A satisfactory world and regional long-range energy supply will depend on prudent political and economic decision making.