The principal elements of the Lutherkirche (church dedicated to Martin Luther) in Düsseldorf are the altar, the ambo or form of pulpit, and the baptismal font. They are all based on the stele, or standing stone, a form which has been used by mankind since time immemorial. They can be seen as “actors” within the church’s interior that form part of the “liturgical drama”. All the items are made of white concrete that has been acid treated to give a durable surface. The altar, which is the central feature of the sanctuary, is made of ten oak boards, ten blocks of concrete and a keystone. There is a pedestal at each of the three liturgical sites for communion, the sermon and baptism. The altar is demountable, so that the space can be converted into a stage area.