Clearly laid out, logical progression from topic to topic, different styles of legendary arrangers included. A must have handbook if you're interested in writing for bigband. It has basic theory, instrument ranges, detailed explanation of arranging process and arranging techniques.
In my humble writing efforts this book is what i turn to when i need to check instrument ranges, theory, techniques or some minor details that are hard to remember.
If you are familiar with jazz theory and the ways to create voicings this book will be easy to follow.