This book is for dedicated fanatics. It allows the storyteller to function on a scale either much larger (such as the management of whole countries and the building of castles) or much smaller (modifiers on hunting depending on which breed of dog you use, for example) than the standard Pendragon campaigns.
This makes the book a valuable tool for experienced players, but less number and detail - oriented ones (such as myself) should be carefull about getting lost in all that information. Another thing to watch out for is the mood, wich on the surface seems quite generic - maybe this was origionally intended as a stand - alone tactical wargame?. Fortunately, they decided to do a guide to role - playing nobles instead, that allows you to do things like design a proper coat of arms or run the twelve nights of Christmas. It also has a full list of Arthurian British annual tournaments, something quite nice to know!.
The only part of the book i didnt much care for was the hunt adventure: some people should really read their beastiaries better...
But still, details like the pictures of the inside of a medival castle or what mood nobles are in on a hunt more than make up for it.
This is not a vital book, but after you have played the game for a while you will come to value it highly: its the most important Pendragon book after "Mystic Tournaments".