California's San Joaquin Valley occupies the southern half of the state's Great Central Valley. Residents of the San Joaquin Valley have not enjoyed the air quality improvements resulting from the Clean Air Act experienced by most of the nation. In fact, the confluence of landform, climate, agriculture and population growth has made the Valley one of the nation's most polluted air basins. There are two forms of air pollution in the Valley, both of which are influenced by seasonal variables such as temperature, wind and atmospheric stability. The first form, associated primarily with summer, is known as photochemical smog or tropospheric ozone. This is the type of air pollution with which those living in congested urban areas are familiar. The second form, associated primarily with winter is known as airborne particulate matter. The primary seasonal influence of airborne particulate matter is the Valley's stable winter atmosphere. The deposition of airborne particulate matter is associated with various environmental impacts involving vegetation, soils and water bodies. Mounting evidence increasingly associates these suspended particles with cardiovascular and respiratory problems as well. The San Joaquin Valley Air Pollution Control District has thus far been unable to reach federal and state attainment levels for airborne particulate matter. In an effort to meet these attainment levels and to avoid strict sanctions, the Air District has formulated a plan to reduce airborne particulate emissions five-percent annually until attainment is reached. The purpose of this Capstone Project is to provide an overview of the Valley's airborne particulate matter problem and the policy and management features of the Air District's plan to resolve it.