Introduction: SETI, the Search for Extra-Terrestrial Intelligence Many researchers in Astronomy and Astronautics believe the Search for ExtraTerrestrial Intelligence is a serious academic enterprise, worthy of scholarly research and publication (e.g. Burke-Ward 2000, Couper and Henbest 1998, Day 1998, McDonough 1987, Sivier 2000, Norris 1999), and large-scale research sponsorship attracted by the SETI Institute in California. Most of this research community is focussed on techniques for detection of possible incoming signals from extraterrestrial intelligent sources (e.g. Turnbull et al 1999), and algorithms for analysis of these signals to identify intelligent language-like characteristics (e.g. Elliott and Atwell 1999, 2000). However, recently debate has turned to the nature of our response, should a signal arrive and be detected. For example, the 50th International Astronautical Congress devoted a full afternoon session to the question of whether and how we should respon
