Mass Market Paperback: 320 pages
Publisher: Tor Books; Reprint edition (2 Jan 2007)
Scalzi's debut novel (and the one for which he won the John W Campbell award for Best New Writer), this is very reminiscent of Joe Haldeman's The Forever War.
The scenario is fairly straightforward: if you're born on Earth, there are two ways off it - either become a colonist (limited to the Third World's population), or volunteer for the Colonial Defence Force. Either way, once gone, there's no coming back, no reporting back either. And volunteers get to go when they're 75.
Once off earth, gone up the space elevators, the volunteers get reconditioned, turned into super soldiers. But, they need to be: there are lots of other races out there, and it seems that humans are in conflict with most of them, for reasons ranging from competition for resources to a desire not to be eaten. It's up to our hero John Perry to stay alive if he can (chances are against him) and to complete the two-going-on-ten years of his service.
There's a sequel coming.