Although patient survival 1 year after kidney transplantation is greater than 90%, infection remains a leading cause of morbidity and death. The risk of infection is related to exposures to potential pathogens in the patient's environment (epidemiological exposures) and the patient's endogenous net state of immunosuppression. Approximately 70% of severe bacterial, fungal, and viral infections occur within 3 months of transplantation. Cytomegalovirus (CMV) infection is still the most important infectious agent following renal transplantation because of its direct effects-morbidity and mortality caused by CMV syndrome and disease, and its indirect effects-contribution to the net state of immunosuppression, which independently increases the risk of opportunistic superinfection. Management of infection in the renal-transplant recipient focuses on preventative strategies. In addition to traditional prophylactic strategies, transplant recipients may benefit from preemptive therapy, ie, therapy directed at patients who are at the greatest risk of developing clinically significant disease, at a time when the risk is maximal. Use of preemptive ganciclovir therapy for the prevention of CMV disease in CMV seropositive renal-transplant recipients during therapy with antilymphocyte antibody is an example of such a strategy. The therapeutic prescription for the transplant recipient is an effective immunosuppressive regimen combined with an anti-infective strategy to ensure its safety.