More than a decade after passage of the Health Insurance Portability and Accountability Act (HIPAA), concerns about the privacy and security of personal health information remain a major policy issue. Now, the emergence of the Nationwide Health Information Network (NHIN) presents deeper underlying privacy challenges, which will require renewed attention from policymakers as federal and state privacy rules need to be revisited. This is necessary because the current framework of privacy laws is not well suited for regulating a transformed health care system, where computer networks supersede conventional communications media.