A Swedish national care programme has provided guidelines for staging, treatment and follow-up of all patients with Hodgkin's disease (HD) since 1985. Between January 1985 and December 1992, 920 patients were reported and followed prospectively. Of a total of 533 patients with stage I and II disease, 484 presented with supradiaphragmatic HD and 49 (9%) with infradiaphragmatic HD. The median follow-up time was 4.3 yr (3.3-10 yr). Significant differences in average age (45 +/- 21 yr and 55 +/- 19 yr), male:female ratio (1.1:1 and 2.8:1) and B-symptoms (25% and 47%) were observed in patients with supra- and infradiaphragmatic HD, respectively. Forty-six patients with infradiaphragmatic HD were treated with a curative intention and 40 (87%) achieved a complete response. Eleven (28%) of the 40 patients have recurred and 8 patients have died of HD. Complete response rates and recurrence frequencies did not differ from those observed in patients with supradiaphragmatic HD. Mortality was, however, significantly higher (p = 0.001) in the infradiaphragmatic group; this was due mainly to poorer effects of salvage treatment in a elderly population. In this population-based study, patients with peripheral disease in stage IA respond well to inverted Y irradiation alone, whereas it appears to be important to give stage II patients chemotherapy or a combined modality treatment in order to avoid unacceptably high recurrence rates.