While much has been written about the clinical document architecture and the challenges on semantic interoper- ability, the modelling of content and the implementation, little attention has been paid to the representation of the medical payload in CDA documents and its implications on usability and accessibility. The authors compare di erent methods to display CDA documents in a cross enterprise environment on the example of the Austrian national patient health record system. Strategies and decisions as well as technological approach and security implications are presented. Finally, a combination of PDF/A-3 and attached CDA doc- ument is proposed as a best practice method for future implementations.