Polychromed and painted wooden retables have been preserved for centuries in churches under uncontrolled environmental conditions. Building defects, climate, sunlight and air-pollution are the most important factors to be examined for their long-term influence. Only extreme defects can be regulated, however; other protection has to be given from periodical care by cleaning and regeneration of coatings in traditional ways. Technical methods vary from part to part according to the substrate and its surface appearance: metals, gloss paint, mat paint, bare wood. Therefore, methods of care vary from mastic to acrylic to water-soluble varnishes. All conservation work is done on site under prevailing environmental conditions and results have so far proved satisfactory over nearly 20 years for 19 great retables in five regions of Austria.