Heart-lung transplantation (HLT) and lung transplantation (LT) are effective treatment modalities for patients with advanced pulmonary parenchymal or vascular disease. Lung transplantation offers potential advantages over HLT, including reduced pretransplant waiting time and improved efficiency of organ utilization, and is currently being offered to patients formerly treated by HLT. To explore the relative merits of these procedures, the authors examined the results in 44 procedures (23 HLT and 21 LT) in 42 patients transplanted at their institution. Heart-lung transplant recipients included 20 adults and three children (ages 5, 5 and 3). Most HLT patients had primary pulmonary hypertension (PPH) (n = 9) or Eisenmenger's syndrome (ES) (n = 8). Twenty-two of twenty-three patients have been long-term survivors (mean follow-up = 17.8 months, Kaplan-Meier survival at 12 months = 85%). Obliterative bronchiolitis (OB) has occurred in five patients (22%), and all have died. Of 21 LTs in 19 patients, nine had obstructive and eight had restrictive lung diseases. Three single-LT (SLT) patients had PPH, and one had ES secondary to a ventricular septal defect. Mean pulmonary artery pressures fell from 55 ± 6 mm Hg before SLT to 21 ± 3 mm Hg after SLT; p < 0.001. Three pediatric patients (ages 4, 10, 17, and 17[re-transplant]) have undergone four SLTs. With mean follow-up of 6.4 months, LT patients have survival at 12 months of 80% (Kaplan-Meier). Lung transplant patients wait a far shorter time for their transplant than do HLT patients (166 vs. 384 days, p < 0.03). Three patients (19%) have evidence of OB after SLT, with one death. By virtue of equal intermediate-term outcomes, shorter waiting times, and better use of donor organs in comparison with HLT, LT should be offered whenever possible to patients with end-stage pulmonary parenchymal or vascular disease. The authors' pediatric LT and HLT experience (7 treatments in 6 patients) is the largest reported to date and demonstrates the utility of these procedures in this group. Chronic rejection (OB) remains the greatest impediment to long-term survival in both LT and HLT pts.