Non-Hodgkin lymphomas (NHL) of the conjunctiva are rare. Radiotherapy is usually considered to be the choice of treatment in such situations. Reported here are 14 cases of conjunctival NHL, treated at the Institut Gustave-Roussy from 1981 to 1988. Mean age of the patients was 53 years. The series comprised 7 stages of IE, 4 stages of IIE and 3 stages of III. Histological types were mostly "low-grade" according to the Working Formulation (9 cases out of 14). The irradiation technique took advantage of a customized facial lead mask and of a direct anterior electron beam. A small cylindrical lead block, hanging some millimetres above the eye, shielded the cornea and the lens. Local control was achieved for 17 eyes treated (out of 19 irradiated), with a follow-up ranging from 5 to 90 months. The 2 relapses occurred in the same patient, and could be treated by a second line irradiation of the same type. Immediate tolerance was good. Late sequelae were rare and actually included 4 cases of cataract which clearly could not be entirely attributable to the treatment. In conclusion, this sophisticated technique appears to be efficient and non-toxic, since it was able to achieve an almost 100% local control rate, together with a very low percentage of late complications.