Emerging communications technologies allow us to potentially reach more individuals with effective health-related advice and information at a very low cost. As we begin a new era of "personalized medicine," advances in consumer health informatics will parallel and eventually merge with those being made in bioinformatics (e.g., genomic information), medical informatics (e.g., electronic medical records), and public health informatics (e.g., disease surveillance). This article discusses access, use, quality, and types of eHealth programming with a focus on the Internet as the initial instantiation of this programming. Also discussed are criteria relevant to the dissemination of eHealth programming in real-world settings. Finally, possible directions for future eHealth research are presented.