[The terrible myth of death]

This paper describes the main tenets of behavioural and cognitive models for the development, triggering and maintenance of mental disorders. These models hold that the processes that generate mental pathology are the same that rule normal behaviour. They also acknowledge the role of biopsychosocial factors in the initiation and persistence of pathology. To the model of the syndrome they oppose the tradition of functional analysis of problem behaviour. In view of the limitations of categorical diagnostic systems, these models opt for case formulations that integrate both the nomothetic and the idiographic perspectives. Cognitivebehavioural models place greater emphasis on the maintaining factors of mental disorders, since they are more accessible for therapeutic change than initiating factors. The paper illustrates these points with some examples of cognitive-behavioural models for different psychopathologies. A difference is made between the causes and reasons for mental disorders. Finally, the article analyses the growing interest in transdiagnostic processes, as well as the potential use of the complex causal network model for conceptualising the relationship between symptoms and dysfunctional processes in psychopathology.