The California Chapter of the International Society of Exposure Science (ISES) was established in 2017.  The Chapter’s aim is to develop and foster a community of Californians working in exposure science and to support ISES in its mission. ISES seeks to foster and advance exposure science related to environmental contamination in human populations and ecosystems; promote communication among exposure analysts, epidemiologists, toxicologists, and other scientists; recommend approaches to substantive or methodological concerns; and strengthen the impact of exposure assessment and analysis on environmental policy.