From its start in medicine the 'biopsychosocial model' was meant to guard the interconnection of its three components. The medical model was regarded as reductionistic. In psychiatry the biopsychosocial model has even gained official status. Nevertheless, it is becoming more and more clear that the model has serious disadvantages. It is confusing, and it divides more than it unites. More specifically, it sheds wrong light on the medical model. In psychiatry, the medical model sets boundaries (e.g. between abnormal and normal), and orders disease on different levels of biological systems. The medical model should be recognized as the unifying force in psychiatry. Without it psychiatry will probably split up. All of this should have important consequences for psychiatric residency training.