This subject heading system has beeen developed for use in FID BAUdigital and its future web services. It covers scientific fields of Civil Engineering, Architecture and Urban Studies with a special section on digitization. This subject classification has been mapped to several other classification systems. The latest version of the subject classification including these mappings is available at https://gitlab.com/fid-bau/terminologie/fid-baudigital-faecherklassifikation/-/raw/main/Subject_Headings_all_mappings.owl.