Brennan's 1987 book Hands of Light: A Guide to Healing Through the Human Energy Field set out her claimed system for perceiving what she described as the human energy field, or aura, in fine layered detail, pairing that description with practical instruction in hands on healing techniques meant to correct imbalances she said she could see directly. The book became a bestseller within the New Age and alternative healing publishing category and remains, decades later, one of the most widely read single texts of the modern energy healing movement, credited by many later practitioners and authors as a foundational influence on their own work.
Brennan presented her perceptual claims as a trained ability rather than symbolic language, though, as with the broader energy healing field, no controlled scientific study has established the human energy field she described as a verifiable physical phenomenon distinct from established human biofields such as measurable electromagnetic activity. The atlas records Hands of Light and the Barbara Brennan School of Healing as the influential modern tradition they are, without asserting the underlying perceptual claims as established fact.
Brennan followed Hands of Light with further books, including Light Emerging (1993) and Core Light Healing (2017), refining and extending her system across a writing career that spanned three decades. Her Barbara Brennan School of Healing developed a multi year certification curriculum that trained practitioners internationally, giving her method an institutional durability beyond her own books that few other individual energy healing authors of her generation achieved.