Before Frawley published the HORARY TEXTBOOK, this book was the best thing going for modern horary. Now that the HORARY TEXTBOOK is on book shelves, this book has become a lot less necessary. HOWEVER, I would not want to dismiss this valuable reference, especially for budding traditional astrologers. You ought to have a copy, but I would save this one for last in the current set of Frawley books. Frawley gives sample charts in this book, and he walks the reader through his analysis of each chart (horary charts, not natal charts). He also discusses some of the niggles and common traps of horary charts. His discussion on reception is great.
And again, where Frawley really soars is his ability to link the beliefs of traditional/Christian astrology (and not just the professional practice) with the modern day astrologer. Frawley is a throwback, not to William Lilly, but to a mindset that existed well before Lilly. He is an articulate, witty, make-yourself-at-home-in-my-mind type of writer. It's a little like having Merlin materialize matter of factly in your living room, ask where you keep your beer, and do you have a cat by any chance, and then he settles down to lecture you on the cosmos as he sees it. So of course you listen to him. I was sad to reach the last page of the book. Merlin disappeared, and I was left in my materialistic, 21st century living room, alone. Predictably, it was raining outside.