Advanced ground and space-based telescopes are discovering new planets around other stars almost daily, but an environmental scientist from England believes that even if some of those planets turn out to be Earth-like, the odds are very low they'll have intelligent inhabitants.

A team of American scientists argue that recent astrophysical discoveries suggest that we should find ourselves in the midst of one or more extraterrestrial civilizations.

If intelligent life exists elsewhere in our galaxy, advances in computer processing power and radio telescope technology will ensure we detect their transmissions within two decades, says SETI Institute senior astronomer Seth Shostak.

Allen Tough argues that if extraterrestrial intelligent life exists in the universe then it will have sent probes out to look for life (similar to Voyage or the the Spirit rover). Seth Shostak looks at his argument and whether or not scientists should be looking for extraterrestrial probes.

According to Harrison, a Professor of Psychology at the University of California at Davis, if we detect a signal from advanced extraterrestrials, there?s a good chance that the basic principles of democracy play a role in their society.

Seth Shostak explains why any extraterrestrials we come into contact with will almost certainly be more technologically advanced than we are.

SETI scientists speculate on whether or not the first extraterrestial intelligence they contact will be machine intelligence or biological intelligence.

Ian Crawford evaluates the evidence for the existence of intelligent life in the universe.

Andrew J. Lepage analyzes previous searches for extraterrestrial intelligence and concludes that the majority of extraterrestrial civilizations are civilizations that are only slightly more advanced than our own.