This document establishes the Reference Standards Portfolio (RSP) for the clinical imaging domain (as defined in Clause 4). An RSP lists the principle health information technology (HIT) standards that form the basis of implementing and deploying interoperable applications in the target domain. An RSP includes a description of the domain, a normative list of standards, and an informative framework for mapping the standards to example deployment use cases. The lists do not include standards that are specifically national in scope. The primary target audience for this document is policy makers (governmental or organizational), regulators, project planners and HIT managers. This document will also be of interest to other stakeholders such as equipment and HIT vendors, clinical and health information management (HIM) professionals and standards developers. The intended usage of this document is to inform decisions about selecting the standards that will form the basis of integration projects in geographic regions or healthcare organizations. For example: What standards to use for capturing/encoding/exchanging certain types of information What standards to use for interfaces between the devices and information systems that support information capture, management, exchange, processing and use What standards to use for specific use cases/deployment scenarios The selected standards, and/or corresponding RSP clauses, might be useful when drafting project specifications. Figure 1 shows the conceptual organization of this document. The top part represents individual HIT standards grouped under semantic, technical and functional interoperability categories. The bottom part shows use cases for example implementation projects with a selected list of standards.