The guideline shows how to reconcile the protection of heritage buildings in their original state and the owner's interest in a fully usable building with modern services. It is a question of installing and operating modern advanced technology in heritage buildings while still preserving the historical structure and cultural value of the building. This problem is especially prominent when putting listed buildings to new uses and improving convenience in historical buildings through technical measures in the following trades: sanitary facilities and media supply, heating and ventilation, electrical technology and lighting, security, conveyance, fire and lightning protection and building automation. The guideline contains practical guidance, recommendations, advice, check lists and evaluation criteria for these areas. It is intended for planners and executors of such construction and conversion works, at owners, users and managers of heritage buildings and at the responsible experts in heritage preservation authorities.