The Bay Area Air Quality Management District (BAAQMD) is a public agency that regulates the stationary sources of air pollution in the nine counties of California's San Francisco Bay Area: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, southwestern Solano, and southern Sonoma. The BAAQMD is governed by a 24-member Board of Directors composed of elected officials from each of the nine Bay Area counties. The board has the duty of adopting air pollution regulations for the district. It is one of 35 Air Quality Management Districts in California.