A review of employment records and tissue specimens of seven workers, reported previously as having occupational dioxin exposure and soft tissue sarcomas, confirms that four workers had employment of 2 to 19 years in the production of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) or trichlorophenol, products contaminated with 2,3,7,8-tetrachlorodibenzodioxin, the most toxic dioxin isomer. Of these individuals, two have confirmed soft tissue sarcomas. In addition three individuals who worked for companies which made 2,4,5-T also have confirmed soft tissue sarcomas. Their employment records do not show specific assignment to 2,4,5-T or trichlorophenol departments; however, one individual worked for 10 d in the production of pentachlorophenol, which is contaminated with different isomers of dioxin. Methodological problems are discussed which must be addressed in the epidemiologic evaluation of the outcome of soft tissue sarcoma.