This was an exciting military SF adventure in the tradition of [b:Starship Troopers|17214|Starship Troopers|Robert A. Heinlein|https://images.gr-assets.com/books/1406457252s/17214.jpg|2534973]. A retiree joins the Colonial Defense Force, rumored to be able to make the elderly young again, and soon finds himself drawn into a much larger universe — one full of conflict — than he expected.

While it's touched upon briefly, I expected a bit more meditation on the psychological toll constant warfare would have on the human mind, but the general mood is kept brisk and light throughout the book. Readers looking for more emotional heft are advised to check out [b:The Forever War|21611|The Forever War (The Forever War, #1)|Joe Haldeman|https://images.gr-assets.com/books/1386852511s/21611.jpg|423] or [b:Armor|102327|Armor|John Steakley|https://images.gr-assets.com/books/1465894856s/102327.jpg|604650]. Despite its different emphasis, Old Man's War is not necessarily a shallow book, however, and fans of those other military SF classics are likely to enjoy this book as well.

Old Man's War works just fine as a stand-alone work of science fiction, but the world presented is interesting enough that the sequel volumes look appealing as well. Recommended for fans of military SF, or old fashioned space opera in general.