Kidney recipients (n = 51) at risk of cytomegalovirus (CMV) disease, and requiring anti-lymphocyte globulin therapy because of biopsy-proven rejection, received high-dose ganciclovir, three times a week, for a total of nine doses. CMV disease was observed in seven (14%) patients within 6 months. Six of these patients were in a group of 45 CMV-seropositive recipients, and one was in a high-risk group of CMV-seronegative recipients. High-dose intravenous ganciclovir, three times a week, seems to be an efficient, safe and easy way to prevent CMV disease in patients treated with anti-lymphocyte globulins for acute rejection.