The goal of the German project “Standardization of Communication between Information Systems in Physician Offices and Hospitals using XML” (aka SCIPHOX) is to provide an XML based information exchange between Hospital Information Systems (HIS) and Physician Office Systems (POS). HL7's Clinical Document Architecture (CDA) was chosen to serve as the “backbone” specification. The CDA is an ANSI approved document architecture for exchange of clinical information using XML. The SCIPHOX proposal specifies the use of the CDA in the context of discharge and referral letters in Germany, taking local needs (insurance information etc.) into account.