Electronic health information exchange (HIE) was a foundational goal of the 2009 Health Information Technology for Economic and Clinical Health (HITECH) Act, but 7 years later we are far from a nationally interoperable health system. Connected electronic health records have the potential to enable fast access to a wealth of clinical data and can deliver a solution to the highly fragmented US healthcare system. In this review, we present a history and background of HIE, including its potential to deliver significant cost savings to the healthcare system. We examine the key components of HIE, including exchanges, the mechanism, and options available to providers. Health information exchange faces significant challenges, ranging from technical issues to lack of a clear goal, but continued policy initiatives and new technologies represent a promising path to providing clinicians with routine, electronic patient data.