After a set of European standards has been prepared by Technical Committee CEN/TC 164 "Water supply" and been adopted as DIN EN standards into the German body of standards (series DIN EN 806 and DIN EN 1717), the task of Committee NA 119-04-07 AA "Häusliche Wasserversorgung" ("Domestic water supply") at the Water Practice Standards Committee (NAW) was to check the content of the standard series DIN 1988 on "Codes of practice for drinking water installations" and to develop a concept for a comprehensive self-contained and consistent replacement document. The European work results do not reach in every case the required standardization depth for the German user groups and therefore it became necessary to prepare German collateral standards which are being published again for continuity reasons under the number DIN 1988 which is already well-known amongst experts. The future standard applies in conjunction with DIN EN 806-2 for the planning of drinking water installations, Installation Type A (closed system) in buildings and on properties. The standard now been submitted on this topic contains additional specifications regarding the consideration of national laws, regulations and the existing German Technical Code and designates the planning basis and the components, apparatus and materials suitable for the erection of the installations. For this purpose, the corresponding editions from the standards DIN 1988-2, DIN 1988-5 and DIN 1988-7, which are required for maintaining the high technical level of drinking water installations recognized in Germany, are used in particular.