The building of medical knowledge-based systems involves the reconstru
ction of methodological principles and structures within the various s
ubdomains of medicine. ACCORD is a general methodology of knowledge-ba
sed systems, and MACCORD its application to medicine. MACCORD represen
ts the problem solving behavior of the medical expert in terms of vari
ous types of medical reasoning and at various levels of abstraction. W
ith MACCORD the epistemic and cognitive processes in clinical medicine
can be described in formal terminology, covering the entire diversity
of medical reasoning. MACCORD is close enough to formalization to mak
e a significant contribution to the fields of medical knowledge acquis
ition, medical didactics and the analysis and application of medical p
roblem solving methods.