Walker et al. recently assessed the value of electronic health care information exchange and interoperability in the US and concluded that a compelling business case exists for its national implementation [1]. These findings are to be interpreted cautiously, and comparable studies are currently underway in other countries. In this context, the openEHR foundation (http://www.openEHR.org) has now published Release 1.0 of the openEHR specification as a common architecture specification for semantically interoperable Electronic Health Records (EHR). These specifications provide a sophisticated, uniform way to model clinical knowledge using archetypes. Archetypes are expressed using the Archetype Definition Language and are based on the openEHR reference model. For semantic interoperability between various Health Information Systems such as EHRs, systematic management of clinical knowledge is essential [2], [3]– no matter what the actual approach and methodology chosen to establish interoperable systems. Archetypes allow clinicians to efficiently agree on the content needed - and increasingly stakeholders in Australia and internationally choose archetypes as the means to define and standardize clinical knowledge. In this context, the aim of this paper is to analyse functional requirements for a web-based system that supports internationally collaborative creation and maintenance of archetypes as well as their systematic management (Domain Knowledge Governance, [4]).