Professor of History John D. Roth will be speaking at the Lancaster Mennonite Conference, "Celebration of Church Life". Friday, March 19, 9 a.m. to 3:30 p.m. at three sessions; Saturday, March 20, 9 a.m. to 3:30 p.m. at two sessions; Sunday, March 21, 3:30 p.m. to 5:00 p.m. for the afternoon worship.