Customs of plain people include:
William Penn, having experienced religious persecution as a Quaker, offered asylum to others who were suffering religious persecution, an offer that many followers of Jacob Ammann accepted, starting with the Detweiler and Sieber families, who settled in Berks County, Pennsylvania, in 1736. Many of them settled near Lancaster, Pennsylvania, which offered some of the most productive non-irrigated farmland in the world. By 1770, the Amish migration had largely ceased.
Nowhere is the Bishop more influential than in decisions concerning the Ordnung. The Ordnung is a largely unwritten code of behavior, covering such items as clothing, vehicles, and the use of technology. The Ordnung varies slightly from congregation to congregation, though is in essence the same. Violations are not considered sins, although wilfulness is considered to be a serious violation of the faith. The Bishop leads the congregation in changing their Ordnung over time. The Bishop may also grant exemptions to the Ordnung. In one instance, one farmer was granted permission to buy a modern tractor since he had arthritis and no children to help him harness horses.
Despite this, the Pennsylvania Dutch are expected to become a smaller percentage of the population, as the sects respond to high prices of farmland by spreading out all over the United States and internationally, and the English population spreads out from Philadelphia into suburban and rural areas. Donald Kraybill believes there are plain sect communities in 47 states.
Among people at least five years old living in Lancaster County in 2000, 11 percent spoke a language other than English at home. Of those speaking a language other than English at home, 64 percent spoke some language other than Spanish. The majority of those people would be Pennsylvania Dutch.
Most plain sects do not admit children to their church, and impose no sanctions on those who do not join, but shun those who fall away from the church once becoming a member. Among Old Order Amish, teenagers who are not yet baptized are not bound by the rules and go through a period of rumspringa, often with certain amount of misbehavior that would not otherwise be tolerated.
Interest in the plain sects also resulted from the movie Witness in which Philadelphia cop John Book, played by Harrison Ford, hides among the Pennsylvania Dutch in an attempt to protect a young Amish boy (and himself) who witnessed a drug killing by a corrupt lawman. The strong characters, the exciting plot, the beautiful pastoral scenery, and the juxtaposition between Book's ways and those of the Amish made it a popular movie. A subplot explores romance between Book and widow Rachel Lapp (played by Kelly McGillis) and the difficulties presented by her religion and his occupation.
The plain sects typically prohibit insurance, and they assist each other charitably in case of sickness, accident, or property damage. Internal Revenue Service Form 4029 allows one to claim exemption to Social Security taxes under certain very restrictive conditions, and members of the plain sects neither pay the taxes nor receive death, disability and retirement benefits from Social Security.
Because of the lack of insurance, limited access to modern transportation, and remote residences of many plain sect members, the State of Indiana did a study in 1972, finding to their surprise that the plain have equal or better access to medical treatment, compared to other citizens.