Cytomegalovirus (CMV) disease in candidates for hematopoietic cell transplantation (HCT) is increasingly observed. Among 22 patients with CMV disease before HCT, the incidence of CMV disease before HCT was significantly higher in patients with severe underlying immune deficiency syndromes compared with patients with hematologic malignancies (P < .001). The lung was the most commonly involved site of infection, followed by the gastrointestinal tract and the retina. Fourteen of 22 patients with CMV disease before HCT responded to treatment and proceeded to HCT; 8 of 22 did not receive an HCT because of fatal CMV disease (n = 2) or other complications (n = 6). Of 14 patients with CMV disease who subsequently underwent HCT, 6 (42%) had CMV disease diagnosed after transplantation despite antiviral prophylaxis or preemptive therapy, and 1 patient had evidence of persistent CMV disease before day 100 after HCT. This proportion was significantly higher than that in patients without CMV disease before HCT during the same time period (day 30, adjusted P = .003; day 100, adjusted P = .02). Thirteen of 14 patients with pretransplantation CMV disease died a median of 36 days after transplantation (range, 19-399 days; adjusted P = .005 compared with CMV-seropositive transplant recipients without a history of pretransplantation CMV disease). In summary, although CMV disease before HCT may be mild and responsive to treatment, it is associated with a high risk of early CMV disease and death after transplantation.