Many research questions in psychiatry can be adequately studied by cross-sectional evaluations of psychopathology at one or more points in time, such as before and after evaluation of various treatment modalities. Other important questions relevant to issues such as diagnosis and prognosis can only be answered satisfactorily by including historical information. There are, however, practically no standardized procedures for obtaining and recording historical information. This paper describes a new instrument, the Current and Past Psychopathology Scales (CAPPS), which can be used for evaluating both current and past psychopathology and social functioning in patients and nonpatients. The coverage includes dimensions of importance in the evaluation of severity of illness, prognosis, and diagnosis. Individuals from a variety of disciplines and with various levels of education have been trained to use it with a degree of reliability and validity satisfactory for research purposes.