The five fixed sources chosen for analysis, based on their importance for the San Diego Basin, are petroleum handling, organic solvent users, aircraft, power plants, and metallurgical processes. A 1975 Nominal Strategy is forecast, representing expected conditions in the San Diego region in 1975 resulting from currently planned control measures. Costs for this and 1975 Medium and Maximal Strategies representing additional control measures are established, based on estimates of the initial investment, which covers purchase and installation of control equipment, and the annual operating and maintenance expenses. Control of all pollutants from fixed sources as established by the 1975 Nominal Strategy will cost about $2.5 million per year; the Medium Strategy, $2.8 million; and the Maximal, $4.6 million. Distribution of costs among various civilian industries and the military is also estimated.