In California, all agricultural pesticide applications are reported to County Agricultural Commissioners for submission to the California Department of Pesticide Regulation. California defines agriculture broadly to include pastures, rangeland, parks, golf courses, and transportation rights-of-way. Homeowner, structural and industrial uses of pesticides generally are not reported. California Pesticide Use Report data can be freely accessed through the California Pesticide Information Portal and used to evaluate integrated pest management (IPM) and inform pesticide policy. California Pesticide Use Report data have been used to document the adoption of new pest management technology, adoption of integrated pest management strategies to reduce specific pesticide risks, and changes in pesticide use behavior motivated by continuing education programs aimed at improved pest management. The data have also been used to provide regulators, such as the United States Environmental Protection Agency, with actual pesticide-use data to replace default assumptions in risk assessment evaluations.