PURPOSE Recent progress in both surgical techniques and therapeutic medication of immunosupression have made lung transplantation a promising option for patients with untreatable diseases of the lung parenchyma. Because preoperatively and postoperatively diagnostic imaging has crucial importance for patient management and clinical decision making we aim to describe imaging features of frequent pathologies in patients after lung transplantation. MATERIALS AND METHODS We reviewed radiological examinations of patients after lung transplantation performed at our institution over a period of four years, and exemplary cases were selected for presentation. Our interest was focussed on both conventional and CT-imaging of postoperative alterations, infections, organ rejection, and pathologies of the airways. Moreover, post-biopsy alterations and lymphoproliferative disorders were documented. Together with clinical information we aimed to give a concise description of specific pathologic entities. Also, the diagnostic impact of more recent techniques such as spiral-CT and thin-section CT should be discussed. RESULTS In cases of early postoperative pathologies and in infections conventional radiography is diagnostically reliable when interpreted together with clinical information. In cases of acute or chronic organ rejection, of lymphoproliferative disorders, of diseases of central or small airways, and for the choice of an appropriate biopsy site, CT has proved to be a valuable imaging modality. Spiral-CT allows airway volumetry in cases of strictures or dehiscence, thin-section CT enables assessment of subtle parenchymal pathologies, notably in cases of chronic organ rejection. DISCUSSION The radiographic findings described below represent specific pathogenetic entities in lung-transplant patients (postoperative alterations, infections, posttransplant lymphoproliferative disorders). Their accurate recognition will have a positive impact on the further clinical history. In the near future, more sophisticated CT techniques should widen our pathogenetic knowledge of alterations in transplanted lungs.