Reduction targets for a desired degree of climate protection are negotiated at the international circuit. Concrete measures for reaching such targets are implemented at the national and city levels. Demonstrated here for electricity use in the commercial sector of the City of Muenster is a “Win-Win Strategy” which, if correctly done will result only in winners. Specifically, it is shown that electricity use between 1990 and 2005 in a Trend Scenario would increase by ca. 25 %, while in the Climate Protection Scenario it could decrease by ca. 23 % due to savings and substitution measures. The benefits, costs, and net gains are computed for different price developments. For a favored variant, the net gain to customers is ca. 66 M DM and that of the city utility – acting as an investor/contractor – is ca. 44 M DM over the period 1996–2021. The monetary savings are calculated by individual uses and user categories. The calculated benefit-loss developments show favorable payback times ranging from 11 to 14 years for the total commercial sector or 2 to 5 years for individual objects. Rough estimates show that over the next 10 years the “Win Win Strategy” could provide 256 additional jobs in the commercial electricity sector of Muenster, and about 700 000 new jobs when projected for Germany as a whole. Additionally, studies show that implementing the electricity efficiency potential in five Western European countries by 2020 could save between 20 and 50 Bil.(billion) ECU, whilst the need for some 90 additional 1000 MW power plants could be avoided. If current commercially available efficiency technologies were used to reach a standard of living equal to that in W. Europe in the late 1970s, the Third World final energy demand would be ca. 1 kW/cap, and in the First World perhaps a little greater. The energetic limit of the ecosphere is estimated to be ca. 1.5 kW/cap at the current world population. Finally, the policy options discussed here can help tap this huge available energy efficiency gold mine by the North and the South alike. The function of the “Win Win Strategy” is to help supply the funds for paving the way toward a sustainable future.