As is the tradition for this conference, the program will include a range of topics and new developments broadly covering the field of atmospheric chemistry. The conference will provide a forum for discussion of both urban and regional chemistry and global tropospheric and stratospheric chemistry. The goal is to bring together scientists working in the laboratory, in the field, and on simulations to provoke discussion towards improving our understanding of the processes that control the composition of the atmosphere. The conference will be preceded by the tenth biennial ACCESS (Atmospheric 91AV Colloquium for Emerging Senior Scientists) colloquium to be held at Brookhaven National Laboratory, New York.