The National Science Advisory Board for Biosecurity (NSABB)'s recommendation to restrict publication of the details of the generation of mammalian-transmissible H5N1 influenza virus is unprecedented. Dual-use considerations indicated that the potential biosecurity risks of a transmissible H5N1 virus with a possible mortality of 50% in humans outweigh the substantial benefits of open and complete scientific exchange in this case, although the benefits include potential early detection strategies for H5N1 viruses with specific genetic markers and control strategies, including development of antivirals and vaccines. It is argued that both the funding agency (the National Institute of Allergy and Infectious Diseases) and the scientists were responding to societal needs and acted entirely responsibly. These studies usher in a new era for life sciences, compelling the research community to confront important decisions: under what conditions should such research be done? How can the principle of full release of information be balanced with the moral imperative to protect the public health?