Proponents of electronic medical record systems cite numerous benefits of their use; however prospective electronic medical record (EMR) purchasers can find relatively little hard evidence these systems will deliver promised or expected benefits. The lack of good information to help identify EMR benefits, estimate and prioritize these benefits, and understand how the benefits are realized is a serious problem for the healthcare industry. This paper describes the most useful current approaches for hospitals to estimate the potential benefits of their EMR systems. Positive and negative aspects of each approach are discussed, as is the question of determining whether a hospital provider could use the approach. Based on this analysis, the article explains the necessity of developing a standardized database of actual provider experience with clinical information system (CIS) benefits, and it describes the initial efforts of the HIMSS CIS Benefits Task Force to create such a database.