What is Reiki Reiki is a spiritual, vibrational healing practice used to promote balance throughout the human system. Reiki does not involve physical manipulation of ingestion or application of any substances, but works with the subtle vibrational field that surrounds and penetrate the body. Reiki is a simple, natural, and safe method of spiritual healing and self-improvement that everyone can use. It can work in conjunction with other medical or therapeutic techniques to help relieve side effects and to help in recovery.