The 'Traditional European Natural Medicine' with the acronym TEN describes an autonomous, rational comprehensible and teachable medical system, which links the traditional roots of medical science with 'modern' insights and hypotheses and further integrates diagnostic and therapeutic developments that are compatible to the TEN system. It is less de ned by the diagnostic and therapeutic methods used, but by the underlying thinking and working model, which basic elements and characteristic aspects will be outlined in the following. TEN is the in Europe originated and further developed correlate to TCM (Traditional Chinese Medicine), for example, or to Ayurveda, and is mainly practiced by natural health professionals in Central Europe, but more and more by naturopathic-oriented physicians as well.