Plain dress is a practice among some religious groups, primarily some Christian churches in which people dress in clothes of traditional modest design, sturdy fabric, and conservative cut. It is intended to show humility and preserve communal separateness from the rest of the world.
The practice is generally found among the following Anabaptist branches: Amish, Hutterites, and Mennonites with the following subgroups: Old Order Mennonites, Conservative Mennonites and traditional "Russian" Mennonites. It is also worn by Old German Baptist Brethren, as well as by Conservative Friends (Quakers), in which it is part of their Testimony of Simplicity; moreover, fundamentalist Mormon subgroups also wear plain dress. Amish, Old Order Mennonites and Conservative Mennonites share the same Swiss-German/South-German Anabaptist tradition.
Among the Amish and other plain groups, plain dress is not considered to be a costume but instead is an expression of their religious philosophy. Plain, simple dress is governed by an unwritten code of conduct, called "ordnung" among Anabaptists, which is strictly adhered to by the Amish and Old Order Mennonites.
Other groups adhering to a conservative dress code include Buddhist and Christian monks, Orthodox Jews, Muslim women, and some Holiness/Pentecostal groups, but these forms of dress normally are not called "plain dress".
Plain dress is attributed to reasons of theology and sociology. In general, plain dress involves the covering of much of the body (often including the head, forearms and calves), with minimal ornamentation, rejecting print fabrics, trims, fasteners, and jewelry. Non-essential elements of garments such as neckties, collars, and lapels may be minimized or omitted. Practical garments such as aprons and shawls may be layered over the basic ensemble. Plain dress garments are often handmade and may be produced by groups of women in the community for efficiency and to ensure uniformity of style. Plain dress practices can extend to the grooming of hair and beards and may vary somewhat to accommodate stages in the life cycle such as allowing children and older people more latitude.