Thanks to a simplification of surgical techniques, single or double lung transplants have expanded significantly in latter years. Infection remains an important cause for morbidity and mortality, more so in early rather than late stages. Bacterial infections cause approximately fifty per cent of all infections. They can be prevented in part by prophylaxis. Infections to CMV have become less frequent thanks to adequate prophylaxis with ganciclovir. Herpetic infections are prevented by acyclovir or ganciclovir. A better control of immunosuppression seems to be associated with fewer lymphoproliferative disorders secondary to the Epstein-Barr virus. Respiratory viruses remain a serious threat for these patients, although infections due to respiratory syncitial virus may be attenuated by ribavirine. Fungal infections are dangerous but prophylactic prescription of azole derivatives have reduced the incidence and severity. Prophylaxis of infections to Pneumocystis carinii is essential, the use of sulfamethoxazole trimethoprim is efficacious against this as well as nocardiosis. Infections to Mycobacterium tuberculosis are often atypical and should be looked for and anticipated whenever possible.