This study is a comprehensive analysis of clean air and climate policy in the Netherlands and Switzerland. Guided by the question «Who can learn from whom?», the author compares story lines, policy instruments and programmes, and actor networks; he very carefully investigates political traditions, problem structures, and the general «philosophy» behind each country's policy. The empirical work focuses on advantages and shortcomings of strategies applied in clean air and energy policy. Traffic policy is of particular interest, since Dutch and Swiss strategies have direct impacts on each other. Empirical observations are embedded in political theories dealing with potential shifts from sectoral thinking towards ecological modernisation, sustainable principles, and network management. The author argues that the real challenge for politics and science is to include normative debate in open policy-making systems and to go beyond simple political, scientific, and economic certainties. However, in view of international target requirements, it is suggested that there is not much time left to experiment with new policy styles.