The essential oils used in aromatherapy practice are derived from living plants, not synthetically created, like perfumes or colognes. They are pure and unadulterated. Essential oils are stored in internal or external secretory structures of plants, which determines how they will be extracted. They can come from the flowers, flowering tops, fruits, zest, grasses, leaves, needles, twigs, resins, seeds, roots or wood of plants.

There are six philosophical principles of holistic aromatherapy. The first is to support the body’s own natural healing. The second is to encompass the whole being and their individuality. The third is to understand the underlying cause of a person’s dis-ease. The fourth is to share knowledge of aromatherapy opportunities. The fifth is to incorporate aromatherapy into daily living for prevention of dis-ease. The sixth principle is to do no harm by using the oils safely.

There are also many books available on aromatherapy, and one solid guide is The Complete Book of Essential Oils and Aromatherapy, by Valerie Ann Worwood.