From the introduction: This game covers negotiations in Sophia as part of the UNECE process in Europe. The LRTAP treaty has come into force and nations are working to reduce SO2 pollution. Negotiations now turn to NOx pollution. This is a more complex problem since the sources are delocalized. Various strategies are proposed. The Germans have already decided they want to follow the USA by requiring catalytic converters on all cars. England, France, and Italy oppose this and offer lean burn engines as an alternative. The Eastern European countries have little possibility of participating in this aspect of the treaty due to the nature of their auto industry and the source of petroleum from the Soviet Union. The Game Book contains a background section on the formation of photochemical smog, the health effects of ozone, leaded gasoline and why it was used in gasoline, and the health effects of lead. This should be sufficient background for a first year college student with no previous college science but with the normal high school science background. This game is derived from the longer Acid Rain in Europe game and normally will be completed in two game sessions of 75 minutes each. Two optional short class activities are provided to help students understand the scientific principles involved. Core documents for the game are contained in the student Gamebook for the Acid Rain in Europe game.