Thirteen institutionalized children from 4-1/2 to 14 years old, diagnosed as autistic, atypical, or childhood schizophrenic, were observed for three years to obtain a detailed description of their speech and language behavior. Case histories were assembled from available medical and psychological data. During a program of experimental relationship therapy, controlled observations were conducted to evaluate each child's linguistic functioning. Although case studies constitute the main contribution of the research, additional findings were as follows: there was a high incidence of first born males of Jewish parents of relatively high socioeconomic status; severe family disorganization had occured in seven of the 12 families; prior to residential placement the children had a wide range of diagnoses; many atypical medical signs were present in the children's birth histories and later diagnoses; there was a significant correspondence between reports of their behavior during the study and reports made previously by other case workers; the majority of the children exhibited indifference, unresponsiveness, minimal or no speech, stereotyped or ritualistic behaviors, hyperactive behavior, and eating and sleeping problems. Observations of speech and language suggested central nervous system dysfunction and the language deficits persisted despite the relationship therapy. (JB)