To determine the effect of prevocational work experience on the severely handicapped, 280 children, aged 14 to 17, were studied. The children were subdivided into three disability groupings (physically disabled, educable mentally retarded, and emotionally disturbed), each of which was further divided into experimentals (E's) and comparisons (C's). The E's received vocational service from three private agencies with workshops 2 days per week during 2 school years. All children were assessed at the start and end of the program and followed up 12 months later. Results indicated that the disability groupings differed markedly in demographic and personal characteristics, in the nature of presenting problems, in their school careers, and in outcomes. The physically disabled benefitted most from the services with the E's having higher potential for employment than the C's; the mentally retarded gained in socialization and interpersonal adjustment, but not necessarily in employability; and the emotionally disturbed did not benefit significantly from the services, except the E's remained in school substantially longer than the C's. Additional findings were that ethnic and socioeconomic status were important determiners of both progress and outcome; the services were least effective with children in the poverty subculture. (Author/JD)