The reported number of bird deaths and subsequent human deaths resulting from exposure to influenza A-infected birds has increased steadily, making front-page news worldwide. Although human viruses do not generally infect birds and bird viruses do not generally infect humans, certain influenza A viruses have historically exhibited an unusual ability to mutate and infect more than one host species. Drawing from sound past and current research, the authors provide an assessment of the real threat of an upcoming avian influenza outbreak and possible pandemic.