Warren and his wife Carol were married in 1979. Warren ministered in a couple of churches in Nebraska and Colorado before he and Carol joined United Indian Missions, with which they have been serving since 1985. During these years of service, Warren has been able to minister in the United States and Canada.
Along with teaching, Warren also co-directs the students' ministry assignments with Steve Roderick.
Warren continues to serve with UIM as a board member and international representative. Warren also serves on boards for the Association of North American Missions and Cedine Ministries.