In the past Ian Sumner has written some very good books for Osprey on the French in WW1. Unfortunately this foray into the Commonwealth forces is less likely to make such a good impression. It's themes are muddled and Sumner clearly expects the reader to have some considerable knowledge ahead of time, But if the reader is knowledgeable, why would he be reading this?
Rather than follow a single topic, like the chronological history of the ANZAC forces he follows themes like "Uniform and Equipment" "Recruitment" "Training" etc and each section on it's own is well written, but the hand offs from section to section are so muddled that they tend to confuse the reader rather then make things clearer. For example the section of Uniforms and equipment goes into detail about the problems hauling ammo, especially artillery shells up to the front line at Gallipoli and the reader has a feeling for the rough gritty Turkish trenches but then the next page starts "Into Action" and you've jumped back several months to when the troops first landed on the Gallipoli Beaches and you've got to start all over again. If the sections were longer it would be easier but considering there are 12 sections in only about 60 heavily illustrated pages there isn't much meat on them.
Also some themes are brought up and never explained. Like how Australian regulars shut down German colonies in New Guinea but there is no real explanation how well these first fights by Australians as their own army went. Were there lessons learned? Who knows, the action is barely an after thought about the troops landing in Egypt. Sumner's handling of the entire Gallipoli campaign seems to believe the reader already has considerable knowledge of that battle because he really just floats it out there, says how important it is for modern Australians but never really gives much in the way of details.
Maps of any quality are entirely missing. He writes about the Australian provinces and the spread out regions of New Zealand but we are given NO idea where any of these are. The reader is supposed to provide their own geographic knowledge. The one map in the book is a close up of the Australian beach head in Gallipoli that you have no clue where anything else is by comparison. Turkey? Other beach heads? Heck, for all the good that map is they could have landed in Michigan!
There is some good in here, but it is for someone who already knows a good deal about the Gallipoli campaign and Australia in general. For a beginner's starting point it is so badly organized you'll be grinding your teeth in frustration over much of it.