Rip-roaring account of the day of battle, arranged in blocks of time roughly from midnight to midnight. Eyewitness accounts describe all the armies and many sections of the battlefield, especially as they fall under fire. The book is organized for emotional impact: We leave the ridge just as things are turning and move to another site of battle, leaving that one just as things are turning, which really keeps the reader reading.
This is not a dry read--the accounts from soldiers and officers in the midst of action are gritty and visceral, and not for the faint of heart or stomach! Of the Waterloo books I've read recently, this is the one that made the physical aspect of the battle most vivid, from the awesome sights and sounds, rumbles and smells, to the mundane tasks of how to sleep in a downpour and where to relieve oneself.
I found the maps, which show where the major people quoted in the text were on the field at the time, both useful and frustrating: Many times it seemed the map one map back was the one that should have been with the chapter I was reading. The way the citations are organized, with all cites for a paragraph grouped together in one note, made it harder for me to determine which reference I wanted to look up later.
Unlike a lot of Waterloo books, this one could be an OK e-book read as the sentences aren't super-dense and there are no pictures; just bookmark the maps because the one you want might not be the one that's closest to that chapter. Also note for e-reading that a section in the endnotes, "Some of the Voices from Waterloo," gives short biographies of many of the people who are quoted; if you forget who somebody is, you can quick check there.