International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / While healthcare industry is striving to achieve e-health systems for improvements in healthcare quality, cost, and access, privacy and security about medical records should be considered carefully. This paper makes a deep study of Public Key Infrastructures (PKIs) and Privilege Management Infrastructures (PMIs) and how they can secure e-health systems. To access resources, e.g. patient records, both authentication and authorization are needed, so public key certificates and attribute certificates are both required to protect healthcare information. From a typical medical scenario, we see not only static but also dynamic permissions are required. Dynamic authorization maybe the most complex problem in e-health systems.