This is not, as one review says, the work of *an* expert, but of many; Hew Strachan is the editor, rather than than the author, and is not even a contributor per se. It may be a little unfair to award an excellent overview of WWI less than 5*, but as another reviewer points out, the fact that it is an overview is a weakness as well as a strength.
The production of the hardback version of this (which is the one I own) is of high quality, which makes the best of the illustrations unlike, for example, the cheap paper used in Random House's Forgotten Voices series. A nice touch is the inclusion of some 2 dozen colour plates. Inevitably, given the lack of colour photography at the time (it was not unknown, but was very much in its infancy at the time), most of these are paintings & posters (4 are modern photographs; 2 of commemorations, one of a genuine Mark V tank; the fourth would appear to be of the only flying original SE5, part of the Shuttleworth Collection). In addition to that, many of the illustrations, both colour & black & white, I have not seen elsewhere. From the point of view of information, it is an excellent overview, on the whole.
Its weaknesses, however, are that, at 350-odd pages it is rather too short, and the "Illustrated" in the title is a bit of a misnomer. Most overview histories of such a large & complex subject run to several hundred pages more than this. It does itself a disservice by trying to compress too much. As for the illustrations, whilst they are reasonably plentiful, I have seen other books with as many that don't call themselves "Illustrated". Therefore, whilst the quality & variety is good, the number perhaps doesn't warrant the claim. Finally, it is worth noting that there seems to be a new edition due out, unsurprisingly, in April 2014, which is a little longer at around 420 pages. I obviously cannot comment on that; for this edition 4* seems, to me, to be a fair review.