Dennis Lewis (1940-) is a non-fiction writer and teacher in the areas of breathing, qigong, meditation, and self-enquiry.
In the book The Complete Idiot's Guide to Taoism Lewis is recommended as a source of instruction in Taoism for people who don't have much time for study and practice. His breathing instruction and practices have also been recommended to augment meditation techniques, to improve singing ability, as a support for recovery from injury, for stress reduction, and for greater calm, presence, and clarity.
In a 2004 critique of New Age literature by Jeremy Carrette and Richard King, he's cited as drawing upon the traditional Taoist interest in longevity but his writing is also categorized as an example of the "flattening out" of subtle cultural and philosophical religious ideas for the commercial and modern self help and personal development movement. In the preface and introduction to The Tao of Natural Breathing, however, Lewis states that his intention in this book wasn't just to explore "the relationship of breathing to health and inner growth" from the Taoist perspective, but also from his "observations and discoveries" from Advaita Vedanta, the Gurdjieff Work, Ilse Middendorf, Feldenkrais, and others, along with scientific principles from anatomy, neurochemistry, and physiology.