Supplementary to the description of diseases at symptom level, the International Classification of Functioning, Disability and Health (ICF), edited by the WHO, for the first time enables a systematic description also at the level of disabilities and impairments. The Mini-ICF-Rating for Mental Disorders (Mini-ICF-P) is a short observer rating instrument for the assessment of disabilities, especially with regard to occupational functioning. The Mini-ICF-P was first evaluated empirically in 125 patients of a Department of Behavioural Medicine and Psychosomatics. Parallel-test reliability was r = 0.59. Correlates were found with cognitive and motivational variables and duration of sick leave from work. In summary, the Mini-ICF-P is a quick and practicable instrument.