Environmental and public health policies protecting Arizona’s groundwater have generated statewide pesticide use reporting systems, while offering opportunities for pesticide research. Since 1996, Arizona Agricultural Statistics Service (AASS), under cooperative agreement with Arizona Department of Agriculture (ADA) Environmental Services Division, has provided data to The University of Arizona Pesticide Information and Training Office in support of research objectives. Since 1995, Arizona has seen a downward trend in agricultural pesticide usage. Preliminary results show a 50% decrease in application acres in Arizona since 1998, adjusted for planting acreage. Analysis of ADA data from 22,425 reports indicated 6,199 (27.6%) of pesticide applications occurred on cotton and 16,226 (63.4%) occurred on other crops. Field size of pesticide applications in 2001 varied widely, ranging from 0.5 to 700 acres per application. Lygus remained the most frequently reported treated pest on cotton, followed by whitefly and pink bollworm. Of active ingredients reported as pesticide application components, 19,423 (54.8%) were applied to cotton. Development and adaptation of the State’s pesticide use reporting system are discussed. Modifications to the database structure are presented. Year-end 2001 statistics are presented summarizing frequencies of applications and reported target pest species in Arizona cotton production. Chemical usage trends and confounding variables are discussed in light of regulatory changes affecting pest management options.