The preservation of historical buildings and energy efficiency do not necessarily have to be in conflict with one another. At the Fraunhofer Center for Conservation and Energy Performance of Historic Buildings in Benediktbeuern, scientists are researching into energy-efficient renovation methods that are suitable for listed buildings. In times of increasing ecological awareness and against the background of the global debate on climate change, the need to save energy in the building sector is growing. This also applies to listed buildings. However, it makes no sense to convert every single historical building into a PlusEnergy house. Bearing in mind the value of the historical monuments and the respective possibilities and implementation constraints, solutions tailored to individual requirements must be found.