While the plurality of approaches is a richness of psychiatry, we need today a unitary framework in which the vast majority of psychiatrists are able to place and recognize themselves. An essential component of this framework should be the awareness that a major outcome of research efforts of the past thirty years is the notion that a simple deterministic etiological model cannot be applied to mental disorders, which instead represent the product of the complex interaction of a multiplicity of vulnerability and protective factors of different nature (biological, intrapsychic, interpersonal, psychosocial). Most current significant etiological research in psychiatry can be accommodated within this framework, thus appearing much less chaotic, inconsistent and fragmentary. This first level of the framework affects in a probabilistic, not a deterministic, way the second one, that of neurobiological, cognitive and psychological intermediate processes. It is unavoidable that different languages be used to describe these processes, but these languages may be translatable into each other to some extent. Furthermore, comprehensive pathogenetic models usually require the integration of different languages. This second level leads, again in a probabilistic way, to the third level, that of symptoms, signs, cognitive dysfunctions and psychopathological dimensions. These are the elements composing the fourth level, the syndromal one. The ICD/DSM formulation of this fourth level is not optimal, but it is the best we have at the moment. Certainly, the fact that two major diagnostic systems exist in psychiatry adds to the confusion and the uncertainty, and should be overcome in the future.