Some common needs for the patient registries, Electronic Health Record (EHR) systems, and clinical research repositories of the future are: semantic interoperability, adoption of standardized clinical terminology, adhoc and distributed querying interfaces, and integration with extant databases and web-based systems. A suite of standards has recently emerged from the consortium responsible for the development and oversight of the protocols of the World-wide Web (WWW). They were conceived to address data integration challenges associated with internet and intranet applications. Many of these standards and technologies are capable of addressing the challenges common to health information systems. In this talk, an introductory overview of these technologies, how they address these challenges, and a brief discussion of projects where they have been used is given.