In view of the current discussions about the diminishing church attendance with its possibilities and opportunities, it has to be conceded that the two Christian churches (i.e. the mainstream Catholic and Lutheran churches in Germany) have taken an avant-garde position - albeit rather involuntarily. Already since the beginning of the 1990s they have been trying to adjust their building estate to the shrinking membership numbers. The Church of the Holy Ghost has been part of the compound of the Dominican Monastery erected in 1233 which since 1958 has housed the office of the Protestant Regional Association (Evangelischer Regionalverband). Today this church is predominantely used as a venue for events. The design of INDEX Architects, which among other functions provides for a strengthening of current public use by building a library within its framework, continues the deliberations of the project "cultural mile Braubachstraße" (Kulturmeile Braubachstraße). Opposite the historical church windows, a shelving structure is to be added, where balconieswill be hanging like swallows' nests serving as islands for reading. The colourful bracings of the balconies as well as the book collection of the Regional Association, amounting to a total of 30.000 publications, correspond to the stained-glass windows. In the church hall itself, a variation of the theme "a house within a house" is to be installed: a walk-in structure with an open top. It offers a focussed, almost contemplative atmosphere for discussions and readings.