The risk of Hodgkin's disease (HD) and non-Hodgkin lymphoma (NHL) was studied in a cohort of 20,245 Swedish pesticide appliers, who had the licence issued between 1965 and 1976. In this cohort 72% were estimated to have been exposed to phenoxy acid herbicides. The cohort was followed-up in the Swedish Cancer Register from date of licence until Dec. 31, 1982 or until death if prior to that date. The mean follow-up time was 12.2 years. A total of 11 cases with HD and 21 cases with NHL were observed compared to 9.1 and 20.8 expected. The relative risks and the 95% confidence intervals were for HD 1.20 (0.60-2.16) and for NHL 1.01 (0.63-1.54). The relative risk rose, but not to statistical significance however, with increased time since licence for both diagnoses.