The studies reviewed were characterized by a lack of attention to scientific methodology and by a divergence in their definition of pathology. About one-sixth of those entering jail in one study reported a history of psychiatric hospitalization as compared with over two-fifths of the subjects in another study. Estimates of behavioral pathology in jails ranged from 35 inmates per thousand in one study to 46 per thousand in another investigation. The modal profile of the referred prisoner in both studies was quite similar: single, committed on a felony charge, and having a history of previous confinement. Functional psychosis was the most common diagnosis in both studies. Self-destructive behavior was found to be more common in jails than in prisons; most self-destructive acts were committed within 30 days of confinement; and there may be links between self-injury and violence, ethnicity, and mental illness. Additional research is needed in the area of psychological and behavioral pathology in jails. An appendix contains term definitions and a chart. A total of 42 references are provided. (Author abstract modified)