Pulmonary toxicity is a well recognised side effect of anticancer agents particularly bleomycin, cyclophosphamide, methotrexate, and busulphan. In contrast this problem has been infrequently reported following MOPP (nitrogen mustard, vincristine, prednisolone, procarbazine) chemotherapy for Hodgkin's disease and has been attributed principally to the procarbazine. We report a further instance of MOPP associated pulmonary toxicity. This case and a review of previously published cases indicate that MOPP chemotherapy may be associated with the development of permanent lung damage as well as an acute reversible hypersensitivity lung disease.