Cooperative healthcare is regarded as one of the major goals for providing adequate health related information to physicians. To achieve this goal, national authorities and large hospital organizations are introducing large scale, standard based transactional EHR systems. Those systems record and distribute a significant amount of medical related data. This raises the concern of information overload for the intended users. The objective is to elaborate on an architecture and consequently a workflow that allows the generation of an automatic patient summary in a standard based IHE XDS environment. A literature review evaluating the current state of research is conducted. Current eHealth projects, laws and technical background are analyzed. An architecture is suggested, prototyped and compared using SAAM (Software Architecture Analysis Method) against alternative approaches. A technical workflow built on IHE XDR and HL7 FHIR observations is suggested introducing two new services within an IHE XDS product for extracting observations from CDA documents and storing the data on domain level scope. The information is published as an OnDemand Document in the IHE XDS infrastructure.