Influenza is a seasonal and pandemic threat to the general population. The effects can be devastating for cancer patients and those who have undergone blood and marrow transplantation (BMT). However, this impact can be minimized. Emergency preparedness is the key to mitigating the impact on the oncology and BMT services. Having a plan that provides a framework of preparedness and outlines steps to take in the event of a community outbreak is crucial. A vigorous immunization campaign for patients, household contacts, and health care staff early in the season is the single most important action. In the midst of an outbreak, the oncology and BMT teams should act to quickly identify patients with suspected infections, move infected patients and staff away from noninfected patients to prevent contact, and decide which patients require prevention or treatment with antiviral agents. Ongoing engagement by the entire team to evaluate the effectiveness of its actions and modify its plan as necessary will ensure success.