The NIMH DISC-IV is a highly structured diagnostic interview that is designed to assess more than 30 psychiatric disorders in children and adolescents; it can be administered by lay interviewers after a minimal training period. The interview is available in both English and Spanish versions. An editorial board was created in 1992 to guide DISC development and to ensure that a standard version of the instrument is maintained. Preliminary reliability and acceptability results of the NIMH DISC-IV in a clinical sample of 84 parents and 82 children (aged 9-17 years) drawn from outpatient child and adolescent psychiatric clinics at three sites are presented. Results of the previous version in a community sample are reviewed. Findings show that despite its greater length and complexity, the NIMH DISC-IV compares favorably with earlier versions. Alternative versions of the interview are in development (the Present State DISC, the Teacher DISC, the Quick DISC, and the Voice DISC). The authors conclude that the NIMH DISC is an acceptable, inexpensive, and convenient instrument for ascertaining a comprehensive range of child and adolescent diagnoses. 5 tables and 35 references