After pastoring at Yokohama Bible Church in Japan, Rev. Iwabuchi began to study and received his M.A. in Missions and M.A. in Communications from the Graduate School of Wheaton College. Rev. Hiro obtained his Master of Theology and Doctor of Missiology from Fuller Theological Seminary. He also has also done research projects at Edinburgh, Oxford and St. Andrews Universities on Celtic Theology.
He has served as pastor of West Los Angels UMC, Japanese American United Church, New York and Blaine Memorial UMC in Seattle. Rev. Hiro officially retired in 2008 and is continuing to serve as part time Japanese language pastor at Blaine.
Rev. Hiro lives with his wife, Hiroko in Issaquah and they have a grown daughter, Maya who lives in Scotland and a son, Luke who lives in Boulder, Colorado.