This is one of the better John Gardner Bond novels. It has a novel plot: Bond not on assignment, but instead the target of a global manhunt. It features some memorable and vicious villains, and a nice amount of plot twists.
Gardner's writing is taut, and we're reminded here that the Bond of the novels may be as suave as the Bond of film, but is considerably more ruthless. He repeats Ian Fleming's classic description of Bond's features as containing a hint of cruelty. Bond's ordeal in this book brings the trait more fully out of him than in other novels.
The first half of the book is particularly good in establishing tension. There are, perhaps, a few plot contrivances, but nothing especially blatant. I've read most of Gardner's Bond novels and would rate this very highly among them.