PROSPR (Population-based Research to Optimize the Screening Process) is an NCI-funded research network which includes 10 diverse healthcare delivery systems across the United States. The goal of PROSPR is to better understand how to improve the cancer screening process (recruitment, screening, diagnosis, referral for treatment) in community healthcare settings in the United States. PROSPR is conducting multilevel observational research to evaluate factors that affect the quality and outcomes of the screening processes for cervical, colorectal, and lung cancer. Each PROSPR Research Center conducts organ-specific research, and also participates with other PRCs to conduct trans-PROSPR research projects. The PROSPR Coordinating Center leads the conceptualization and development of measures of health system-level factors that impact the screening processes, as well as measures of screening process quality. These measures are being used in trans-PROSPR research projects.