Horse-and-buggy groups have retained a rural lifestyle, with farming as an important part of their economy. Most horse-and-buggy Old Order Mennonites allow the use of tractors for farming, although some groups insist on steel-wheeled tractors to prevent their being used for road transportation. Some traditional groups, like the Orthodox Mennonites and the Noah Hoover Mennonites, still till their fields with horses. The horse-and-buggy people stress separation from the world, excommunicate, and normally shun in a strict manner. All Old Order Mennonite groups meet in meeting houses or church buildings (when they have full-fledged congregations), contrary to the Old Order Amish, who meet in the homes or barns of their members.