Patients will be pre-medicated with Diphenhydramine 1mg/kg IV (max 50 mg) and Acetaminophen 10mg/kg po (max 650 mg). EBV specific T cells will be given by intravenous injection over 1-10 minutes through either a peripheral or a central line. Outpatients may be treated in the clinic. Monitoring will be undertaken according to institutional standards for administration of blood products with the exception that the injection will be given by a physician. Anti-emetics in appropriate dosage for each patient will be prescribed as necessary. Patients will receive supportive care for acute or chronic toxicity, including blood components or antibiotics, and other intervention as appropriate.