content: This book is definately a must for anyone studying or wants to know more about essential oils. I used this book as a bible during my Diploma of Aromatherapy course, and I still find it a valuable tool for this modality, as it covers everything from where the plant originates from, its chemical properities, effects on the mind, body, skin, blending. I highly recommend this book for any aromatherapy enthusiast. A must on the bookshelf.