For the purposes of this study, severely disturbed juvenile offenders are those who suffer from forms of mental illness such as schizophrenia, psychotic depression, and organic brain syndromes, and who manifest delusions, self-mutilation and other severely self-destructive behavior, hallucinations, seriously impaired judgment, and other thought disorders. The number of studies that provide estimates of the number of seriously disturbed juvenile offenders is small. The evidence available suggests that these youths are a relatively small percentage of the general population of juvenile offenders. However, the severity of these youths' illnesses, the seriousness of many of their offense histories, and the frequency with which they fall between the administrative boundaries of departments of corrections and mental health call for a concerted effort to design programs and services suited to their needs. Development of adequate services has been impeded by disagreement about whether mental health or correctional State agencies should assume primary responsibility for these youths. Further obstacles are philosophical differences of opinion about the type of treatment that should be provided for these youths, and the high cost of care for these youths. The development of adequate care for the severely disturbed juvenile offender depends first of all upon the determination of which agency is responsible for the care. However, whatever agency is responsible, attention must be given to the quality of staff, the services provided, and the quality of facilities used. Other issues to be considered are intake criteria and the problem of referral, due process and program design. Twenty-two notes are provided.