For many years the federal government funded the Search for Extraterrestrial Intelligence (SETI), later popularised by Carl Sagan’s novel Contact and the movie starring Jodie Foster. Though in actuality SETI never did make contact with signals from an alien civilisation, the search continues to this day through privately funded endeavours. How likely is it that intelligent life exists elsewhere in the universe? This is the intriguing question that has prompted William Burger’s illuminating and absorbing exploration of the unusual circumstances surrounding life on earth. Burger’s enlightening evaluation of evolutionary and cosmic history, full of fascinating details, shows that the human achievement may be unique in our galaxy.