Two international classifications currently dominate research and clinical practise; the International Classification of Diseases (ICD)-10 and the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV. Both classifications provide detailed descriptions of all the main psychiatric syndromes, personality disorders and other disorders of behaviour or function. The first comprehensive nosology covering an entire range of diseases and including a classification of mental illness was produced by the newly formed World Health Organisation (WHO) in 1948. The WHO has the responsibility to produce regular revisions of the ICD for international use. Disorders in ICD-10 are arranged in groups according to major common themes or descriptive likenesses. DSM-IV has more categories than ICD-10, which may reflect the requirements of the health care system in the United States. The International Personality Disorder Examination (IPDE) assesses the phenomena and life experiences that are relevant to the diagnoses of personality disorders in DSM-IV and ICD-10.