still made by groups of experts, now are openly scrutinized by other governmental bodies, the general public, advocacy groups, and the media. The array of environmental and health and safety laws enacted during the past three decades often provides ample opportunity for public involvement in many parts of the decision-making process that previously were conducted in private. The possibility of legal challenges always exists.

In light of the public's past response to other controversies involving science and technology, it is possible that environmental and quality-of-life issues will be raised in the context of a Mars sample-return mission. If so, it is likely that the adequacy of NASA's planetary protection measures will be questioned in depth. The most effective strategy for allaying fear and distrust is to inform early and often as the program unfolds. Acknowledging the public's legitimate interest in planetary protection issues, and thereby keeping the public fully informed throughout the decision-making process related to sample return and handling, will go a long way toward addressing the public's concerns.