Hakuun Yasutani was a Sōtō priest and the founder of the Sanbo Kyodan, a lay Japanese Zen group. Through his students Philip Kapleau and Taizan Maezumi, Yasutani has been one of the principal forces in founding western (lay) Zen-practice.

Japanese Zen refers to the Japanese forms of Zen Buddhism, an originally Chinese Mahāyāna school of Buddhism that strongly emphasizes dhyāna, the meditative training of awareness and equanimity. This practice, according to Zen proponents, gives insight into one's true nature, or the emptiness of inherent existence, which opens the way to a liberated way of living.