Fifty male AIDS patients with Kaposi sarcoma and 50 matched controls were interviewed about occupation, exposure to pesticides, Vietnam service, smoking habits, etc. No difference in use of pesticides was seen. One case but no control had served in Vietnam and was thereby exposed to agent orange. Dioxins are known to be immunosuppressive in animals. No significant difference in exposure to dioxin-containing products was found between cases and controls, however. Of interest was the fact that four cases but no control were occupationally exposed to hair dyes, some of which have been reported to be carcinogenic.