This international conference will provide a technical forum on advances in the scientific understanding of the effects of aerosols on urban, regional, continental, and global-scale haze and the radiative balance. The conference will take a multipronged approach by encouraging scientific dialogue (e.g., related to measurements, modeling) as well as including presentations addressing regulatory and policy issues. This year, we will be highlighting planned sessions on biomass burning and the effects of wildfire on air quality and increasing concerns of the effects of atmospheric nitrogen and carbonaceous material on haze, climate change, and nitrogen deposition on ecosystems