Air pollution remains a major environmental issue despite many years of study and much legislative control. In rec~nt times, pollution on a global scale has become of particular concern. The gradually changing con- centration of trace gases in the global troposphere due to man's activity is becomming a matter of serious concern. No scientist would dare to pre- dict in detail the consequences of this gradual change due to its immense complexity involving social and economic factors and near countless chemical and phjsical cycles in our biosphere. In this chain of processes, the transport of pollution is an important factor, but only a factor. Therefore, I would like to emphasize that the mOdelling of atmospheric transport is becoming more and more an activity which fits into larger frameworks and can no longer be exercised as a single step, which bridges the gap between emissions and policy measures. This is also reflected in the topics and papers which were presented at this conference. The topics were: - emission invetories for and source treatment in air pollution dispersion models; - modelling of accidental releases; - regional and global scale dispersion mOdelling; including boundary layer-free troposphere exchange processes and subgrid scale parameter- isations; - model verification and policy implications; - new developments in dispersion modelling and theory. 56 papers were presented in these sections. While many posters were dis- cussed in a special session.

Air pollution remains a major environmental issue despite many years of study and much legislative control. In rec~nt times, pollution on a global scale has become of particular concern. The gradually changing con- centration of trace gases in the global troposphere due to man's activity is becomming a matter of serious concern. No scientist would dare to pre- dict in detail the consequences of this gradual change due to its immense complexity involving social and economic factors and near countless chemical and phjsical cycles in our biosphere. In this chain of processes, the transport of pollution is an important factor, but only a factor. Therefore, I would like to emphasize that the mOdelling of atmospheric transport is becoming more and more an activity which fits into larger frameworks and can no longer be exercised as a single step, which bridges the gap between emissions and policy measures. This is also reflected in the topics and papers which were presented at this conference. The topics were: - emission invetories for and source treatment in air pollution dispersion models; - modelling of accidental releases; - regional and global scale dispersion mOdelling; including boundary layer-free troposphere exchange processes and subgrid scale parameter- isations; - model verification and policy implications; - new developments in dispersion modelling and theory. 56 papers were presented in these sections. While many posters were dis- cussed in a special session.