This book is the continuation of Red Mars, it shows how Mars has been changed by the people and how the people have been changed by Mars. It is an extremely good book, filled with a good plot, some science and the socio-poltical observations I have come to expect from Robinson. Be warned though, this is NOT a light read, in fact it is often very heavy going and the non-scientifically minded might get confused by some of the explanations. However, if you can make your way through it then it is an enjoyable and rewarding read.