Recurrence of the original disease in the transplanted organ is well reported in renal transplant recipients. There have been no previously fully documented cases of recurrence of the original disease after lung transplantation. We report a patient who underwent single-lung transplant in 1990 for end-stage respiratory failure secondary to biopsy-proved giant cell interstitial pneumonitis (GIP). There was no further industrial exposure. Surveillance bronchoscopies and biopsies post-transplant demonstrated eosinophils and giant cells in the bronchoalveolar lavage of both lungs, and in biopsies of the transplanted organ. Two years after successful transplantation the patient deteriorated and underwent open lung biopsy, which demonstrated not only bronchiolitis obliterans but also the classic features of GIP. There was no evidence of inorganic particles in the transplanted lung. Autopsy confirmed the presence of numerous giant cells characteristic of GIP with associated fibrosis throughout the transplanted lung. Although tungsten and other inorganic particles were again demonstrated in the native lung, there was no evidence of tungsten particles in the transplanted lungs. We believe that this case documents recurrence of the original disease after lung transplantation. The absence of unusual inorganic particles in the transplanted lung in the face of the classic picture of GIP is highly suggestive of an autoimmune mechanism for this occupation-associated disease. The appropriateness of transplant in the management of this lung disease should be reviewed further.