I loved this book on Herbs. One of the very first I ever bought. Breaks everything down very nicely, into herb type and body system. Was easy to understand and follow. I also found it too be well grounded. Was impressed by the willingness to admit when herbs may not be enough and other anvenues should be explored.
Reading this book for a Medicinal Plants and Herbology course; David throws in little bits of his personal philosophy while describing in good detail the purpose and use of a wide variety of herbs in the medical world.
I've been studying herbalism for a few years now. This should have been my first reference. This does the best job I've seen of covering actions and body systems succinctly.