At the German Heart Institute Berlin the introduction of information technology to clinical practice went an unusual way. Instead of serving the administration exclusively, the first thing computerized was the patient admission, the medical documentation and text processing. This is important to note because it is the medical documentation that contains or causes almost all data, that will later on be used for administration purposes. Medical documentation however sets many more obstacles in the way to computerization than administrative applications. To overcome these problems the BAIK system is used. More than 2000 catheter and 3500 surgery procedures documented each year with BAIK prove the viability of the system for day-to-day operations. That it is still used, despite the fact that it was designed in the sixties, makes a review of the original design criteria a learning experience for new developments in computer applications for medical documentation.