Most economic studies of picture archiving and communication systems (PACS) to date, including our own, have focused on the perspectives of the radiology department and its direct costs. However, many researchers have suggested additional cost savings that may accrue to the medical center as a whole through increased operational capacity, fewer lost images, rapid simultaneous access to images, and other decreases in resource utilization. We describe here an economic analysis framework we have developed to estimate these potential additional savings. Our framework is comprised of two parallel measurement methods. The first method estimates the cost of care actually delivered through online capture of charge entries from the hospital's billing computer and from the clinical practices' billing database. Multiple regression analyses will be used to model cost of care, length of stay, and other estimates of resource utilization. The second method is the observational measurement of actual resource utilization, such as technologist time, frequency and duration of film searches, and equipment utilization rates. The costs associated with changes in resource use will be estimated using wage rates and other standard economic methods. Our working hypothesis is that after controlling for the underlying clinical and demographic differences among patients, patients imaged using a PACS will have shorter lengths of stay, shorter exam performance times, and decreased costs of care. We expect the results of our analysis to explain and resolve some of the conflicting views of the cost-effectiveness of PACS.