The guideline VDI 3814 applies to equipment, software and services for automatic control, monitoring, optimisation and operation and for the energy-efficient and reliable operation and management of building services (GA). Building automation is a prerequisite for comprehensive building management. As the international standard DIN EN ISO 16484 does not contain all the regional requirements, VDI 3814 takes over the task of defining the requirements for building automation and control systems (BACS) which are standard in Central Europe (exception: requirements for electrical safety). The guideline VDI 3814 Part 1 defines system principles for BACS.