This paper gives an overview of projects completed on the topic of electronic referral in healthcare. The first referral projects were based on standardized EDI-communication. The same basis is still used in many projects, but these are slowly being replaced by web-based solutions with possibilities for decision support and booking. The time from initiation of the first services to high volume use seems to be very much related to how well the new solutions fit with the general practitioners and specialists work practices, and if there are obvious benefits for the communication partners. High volume national services seem to require both political support and pressure. Some of the projects have not paid enough attention to sociotechnical approaches.