An illusion in the minds of many is that Center for Certification of Health Information Technology (CCHIT) certified EHR systems are interoperable. To many, this would be one of the major if not sole reasons for CCHIT to exist. The surprising reality is that this is something that CCHIT certification does not currently include. Another reality is that 'interoperability' is a loaded term that is very difficult to define among proprietary EHR's.