Implementing electronic health record (EHR) systems in the next few years is on the agenda for many healthcare organizations. Before investing in an EHR system, however, decision makers need to identify and measure the benefits of such systems. We propose using a system dynamics (SD) approach to measuring the benefits of EHR systems. Using an SD approach, it is possible to map complex relationships among clinical processes in hospitals into a model by which one can dynamically measure the effect of any changes in the parameters over time. Simulation of EHR implementations using an SD model produces useful data on the benefits of EHRs that are hard to obtain through empirical data collection methods. The results of an SD model can then be transformed into economic values to estimate financial performance. This paper presents an example of an SD model and its application in EHR decision making.