Mental health services in many countries undervalue the special needs of people with auditive disorders. The diagnosis and treatment of mental health issues in this group of people, however, requires special skills in communication and knowledge of language and, relevant medical, psychosocial and cultural issues related to the auditive disorder. The great variation between these aspects complicates the psychiatric diagnostic process. In addition, there is a remarkable diversity of psychiatric syndromes and special target groups; these include deaf and hard of hearing patients, deaf-blind patients, mentally retarded patients, patients with brain damage, immigrants, forensic patients, patients with special medical problems and patients who have been physically and sexually abused.In several European countries specialised services have been developed with multidisciplinary teams. These teams observed difficulties in the diagnostic process and classification. Neither were psychiatric and psychological scales reliable nor validated, because they needed to be adapted to the language skills of the patients. Symptoms such as auditive hallucinations presented differently. In special causes of deafness such as prenatal Rubella, special symptoms occurred.In this lecture, an overview of these diagnostic problems will be presented illustrated with case-histories. A research project into the validity of screening lists for mental disorders and autism in mentally retarded deaf people will be discussed.