Cytomegalovirus (CMV) is the single most important viral pathogen in organ transplantation. Treatment strategy for CMV infection and disease is not well established in transplantation. We report a case of primary CMV infection and two relapses in a woman with a liver transplant in whom spontaneous clearing of the second CMV relapse was seen. A 23 year-old CMV-seronegative woman received a liver transplant with a CMV-negative organ. Six weeks after transplantation she had her primary CMV infection proved by seroconversion and virus isolation. She had no clinical symptoms. Treatment with ganciclovir for five weeks resulted in declining CMV-antigen positive cells from 300/200.000 PMNs to CMV-antigen negativity. Only a slight antibody response was seen. At week 13 the first relapse occurred evidenced by antigenaemia. Ganciclovir was reinstituted for six weeks resulting in reduced antigenaemia. At week 22 liver biopsy was performed due to slightly elevated ALAT. The biopsy showed evidence of focal CMV hepatitis and blood analysis showed 120 CMV-antigen positive cells/200.000 PMNs. In spite of this, ganciclovir was not reinstituted, but the immunosuppressive treatment was reduced to a minimum to stimulate the patient's immune response to CMV. During the following months the patient gradually developed IgG antibody, cleared the antigen and levels of liver enzymes returned to normal. We suggest that ganciclovir treatment, may be omitted in cases of relapse with minimal clinical symptoms, slight antigenaemia and a beginning antibody response and that, the immunosuppressive treatment should be reduced instead. Such an approach requires careful clinical monitoring of the patient.