There are several different ways in which a health information exchange can be implemented. In the most common model, the patient medical record information is stored at the home institution or physician’s practice where it was created. When the patient is admitted to a hospital or emergency department or even goes to see a new doctor in another practice that also participates in the exchange, the new hospital or new physician can easily connect to the health information exchange electronically to pull relevant information on the new patient from other hospitals and doctors.Health information exchanges vary in scope, from national to regional to local, such as sharing within a city. Health information exchanges can also be developed within a health care system to connect affiliated hospitals and physicians in their network. About 40 percent of hospitals and health systems have incorporated health information exchange capabilities into their technology strategy.