David Schiller is the co-author of seven internationally published books on the use of essential oils. He has spent over twenty-five years studying and researching the benefits of plant oils, and determining their practical uses and applications. Along with Carol Schiller, David has been instructing classes and training workshops for companies, colleges and other educational organizations since 1989. Carol Schiller is the co-author of seven internationally published books on the use of essential oils and cofounder of the International Aromatherapy and Herb Association. She has spent over twenty-five years studying and researching the benefits of plant oils, and determining their practical uses and applications. Along with David Schiller, Carol has been instructing classes and training workshops for companies, colleges and other educational organizations since 1989. She has also been a featured presenter at international conferences.