The Scandinavian countries are all among the minority of the world's nations that have established a national health network infrastructure. These networks provide a secured communication environment for health professionals, mainly in hospitals and local health services/GPs. Despite serving similar requirements, these national infrastructures differ in several aspects: organizational extension, choice of carrier technology, IP addressing and NAT strategy, DNS implementation and QoS support. Initiatives to interconnect these national health networks in Scandinavia date several years back, and today the Danish health network has a number of cross-border connections, including VPN tunnels to the Swedish and Norwegian health networks. However, limitations in the connecting technology, and scalability issues related to technological architecture, pose limitations on the cross-border service provisioning. The thesis investigates the differences in technical infrastructure, discusses consequences of these differences, and suggests modifications to harmonize the technology among the national health networks involved. Some of these suggestions may even have merit within national borders, as they can be seen to address scaling issues in intranetworking in general.