National policymakers are considering whether to make major long-term investments in electronic medical record (EMR) systems. The matter of rising health care costs is never far from any health care debate, and the prospect for EMR systems to decrease costs is a potential selling point. The paper by Richard Hillestad and colleagues presents a well-documented analysis of the potential costs, savings, and other benefits of widespread adoption of interoperable EMR systems. It focuses on the potential savings such systems could yield. Here I examine the main components of their argument and question whether such savings could ever be realized.