From Belfast, Northern Ireland, Paul Haller left home in 1971, lived in London for a year, then traveled throughout Europe, the middle east, Russia, and Afghanistan. He ended up in Japan, where he lived for a year and was introduced to Zen. Then he traveled throughout southeast Asia. He was ordained a Buddhist monk in Thailand, where he spent six months sitting in a remote cave.

Moving to Tassajara Zen Mountain Center in 1974, Paul was ordained as a priest by Zentatsu Richard Baker in 1980, who gave him the name Ryushin Zendo, "Dragon Heart, Zen Way." In 1993 he received Dharma Transmission from Sojun Mel Weitsman.

Founder and formerly Director of Outreach at SFZC, Paul is interested in finding ways of expressing our practice in society, both as compassionate service and making it available to as many people as possible. He became abbot of Zen Center in 2003.