Epstein-Barr virus (EBV) is a human herpesvirus that is ubiquitous in both developed and developing countries. In the latent form, EBV expresses a restricted set of nuclear and membrane antigens. EBV has been associated with a wide variety of lymphoid neoplasms. B-cell lymphomas that have been associated with EBV include Burkill lymphoma (BL) and malignant lymphomas arising in immunocompromised patients (including patients with AIDS, congenital immunodeficiency, and iatrogenically induced immunodeficiency). T/natural killer (NK) cell lymphomas that have been associated with EBV include nasal T/NK lymphoma as well as several rerer entities. Approximately 40–50% of cases of Hodgkin's disease (HD) are EBV-associated in developed countries. Although data suggest that EBV contributes to the pathogenesis of many of these neoplasms, no direct evidence links EBV to the eulogy of any of these lymphomas.