An important research finding in the life sciences has galvanized and divided the international scientific and security communities. The creation of a version of H5N1 influenza virus (bird flu) that can be transmitted by respiratory droplets or aerosol between mammals raises hopes that a vaccine can be made – and fears that humans will speed up the process by which this new virus will be unleashed. Research has been suspended while scientists debate the proper course to take. Any solution must be part of a larger regional effort to address biosafety and biosecurity concerns.