We are not alone in the universe. A few years ago, this notion seemed farfetched; today, the existence of extraterrestrial intelligence is taken for granted by most scientists. Even the staid National Academy of Sciences has gone on record that contact with other civilizations is no longer something beyond our dreams but a natural event in the history of mankind that will perhaps occur in the lifetime of many of us." Sir Bernard Lovell, one of the worlds leading radio astronomers, has calculated that, even allowing for a margin of error of 5000%, there must be in our own galaxy about 100 million stars which have planets of the right chemistry, dimensions, and temperature to support organic evolution. Unless we are terribly conceited, we must assume that the "others" are far more advanced than we are. Even a 50 year gap would be tremendous; a 500-year gap staggers the imagination, and as for a 5000-year gap... It is quite possible that "others" have satellite probes in space, retransmitting to "them" anything that sounds nonrandom to the probe. But they have probably called us several thousand years ago, and are waiting for an answer; or worse yet, they have given up; or, more probably, they have reached such impressive technological advances that they have destroyed themselves. After we resolve our pressing scientific questions, it might be appropriate to make discreet inquiries as to how we could live in harmony and peace with our fellow man. [We] must keep a level head ... and be prepared to cope with problems the like of which he has never seen - out of this world, so to speak.