There are here described a number of basic principles underlying an effective clinical interview in psychiatric difficult situations (violent or suicidal patients, victims of serious physical and psychological damages, authors of inadequate or anti-social requests to the therapist). The aim of the present study is to provide the psychiatric operator with useful skills for the optimal management of the interview in difficult situations both at diagnostically and therapeutically level. The methodology was based on examination of the literature and personal experience of the authors. The authors highlighted 18 working hypothesis that may represent beneficial instruments in situations of difficult psychiatric interview. Further studies will deepen under the clinical, actuarial and statistical validity the principles covered in various clinical and crisis situations with difficulty to the interview, in relation also to specific types of patients for a more updated training of the operators in the field of mental health.