The first thing to keep in mind when thinking about interoperability is not a particular standard or technology, but motivations for instituting data exchange. Widescale interoperability has been technically possible for more than 20 years, and major hospitals have had data worth exchanging for at least that long. But as with EHRs, exchanging health data has stalled due to conflicting and backward incentives.

Historically (with a few notable exceptions) most healthcare institutions have found little motivation for interoperability. There is a lot of motivation to profess interest in healthcare interoperability, which costs nothing. This creates confusion among those outside the healthcare industry. For example, if the hospital CEO says that interoperability is “critical,” why is there no health data being exchanged?