Universität Bremen TZI In a protocol or an application environment, it is often important to be able to create unambiguous identifiers for some meaning (concept or some entity). Due to the simplicity of creating URIs, these have become popular for this purpose. Beyond the purpose of identifiers to be uniquely associated with a meaning, some of these URIs are in principle _dereferenceable_, so something can be placed that can be retrieved when encountering such a URI. The present -00 version is a stub to draw some attention to the opportunity that this pattern would benefit from a common description, documenting its benefits and pitfalls, and some mitigations for the latter.