This project involves the scientific coordination and administration of the International Global Atmospheric Chemistry (IGAC) Core Project of the International Geosphere-Biosphere Program (IGBP). This work includes: (1) coordinating the Scientific Steering Committee (SSC) and scientific Activities of IGAC, including meeting arrangements, travel, correspondence, and record keeping where appropriate, (2) developing and subsequently updating descriptions of the ongoing efforts and future plans of each of the IGAC Activities, (3) providing an international information and communications center for IGAC, and (4) fostering cooperation between IGAC's cosponsors (IGBP and the IAMAP Commission on Atmospheric Chemistry Global Pollution (CACGP)) and between IGAC and its related IGBP Core Projects, other ICSU- sponsored global change research programs (e.g., WCRP), and other relevant international bodies (e.g., WMO).