Once viewed as an alternative approach, preventive medicine is now in the mainstream, having been embraced both by doctors and by established health plans. It has been the aim of The Wellness Letter, published at the University of California, to inform the general public about preventive medicine, and the creators of that newsletter have edited this home reference book, which uses straightforward, non-technical language. It sets out to dispel misconceptions about diet and exercise, to explain the link between lifestyle and staying well, to report on ways of coping with stress, to explore environmental and public health concerns which can affect personal health and to recommend alternative health measures.