Given new and emerging standards and requirements in Europe regarding energy performance of buildings (see, for example, EPBD 2002/91), it has become increasingly important to improve the energy effectiveness of building operation. Toward this end, efficient daylight-responsive systems for illumination of buildings (including installation of automatic lighting control systems) can provide a significant contribution (EN 15193). At the "CUnEdI: Centro Universitario Edifici Intelligenti" of the University of Trento, study and research activities have been curried out in order to define a new methodology for the design of lighting systems, using automation technology to optimize the energy demand. In this paper, we present the application of this design method and the final results of the yearly energy saving amount for a specific case study: the MART-Museum of Modern and Contemporary Art of Trento and Rovereto (Italy). The lighting control system of the museum was operated in a conventional manner: luminaires was switched on and off manually by the staff in a central station control. In order to improve the energy efficiency of the lighting system, different automated control regimes were implemented and monitored over the first year of installation: occupancy detectors, illuminance sensors, and dimming actuators, have been installed and programmed specifically for each scenario, defined on a temporal and by event definition. We compared the lighting energy use in the museum operated in the traditional manner and implemented with the automated scenarios: the 50% of lighting energy has been saved, covering in one year the installation cost.