Communicating about the 2009 H1N1 vaccine presented unique challenges. These included priority audiences which differed substantially from those recommended for the seasonal flu vaccine; a vaccine availability schedule that was out of sync with demand; consumer concerns raised by the rapid development and testing of the vaccine; and intense and changing media coverage. These and other factors made for a volatile and unpredictable communication environment. CDC used qualitative and quantitative research methodologies as well as traditional and online media monitoring to track consumer knowledge attitudes and behaviors. Data were analyzed in real time to inform changes in communication and media strategies and tactics. Notable changes in attitudes toward vaccination, awareness of ACIP recommendations, and intentions to seek vaccination were documented in the months leading up to the flu season. The interplay between perceived risk of disease and safety of the 2009 H1N1 vaccine led CDC to treat communication about the disease (increasing risk perception) differently from the vaccine (reassuring concerned consumers). Much was learned throughout the months of designing, implementing and assessing a multi-faceted communication and media campaign that targeted both specific populations and the overall public. In this session, the speakers will identify and detail some of the major “lessons learned” in designing and implementing communication, messaging, news media and social/digital media strategies and tactics. These lessons have applicability not only to future influenza immunization-related communication efforts but to a wide range of health promotion and disease prevention efforts.