Influenza vaccination is the provision of annual vaccine against influenza with inactivated influenza virus. Several organizations have published guidelines on vaccination of hematopoietic stem cell transplantation (HSCT) recipients (see Center for Disease Control and the European Bone Marrow Transplant Group), and National Comprehensive Cancer Network (NCCN) guidelines provide general principles regarding vaccination use in patients with cancer. Live attenuated vaccines have the potential to cause disease in compromised patients, however other vaccines are safe. The NCCN recommends patient vaccination at least two weeks before receiving immunosuppressive or cytotoxic therapies. It has been noted that influenza infection causes substantial morbidity and mortality in patients with cancer. Full recommendations regarding vaccination types and timing can be found in NCCN guidelines for prevention of infection.