Restoration and conservation treatments of paintings have already been documented in detail since the middle of the 19th century. Looking back on this long tradition, the Doerner Institut today has an extensive body of historical restoration and conservation reports that provide valuable information if new treatment is necessary. Compared to the purely written records of the 19 th century, today’s documentary techniques include a wide range of methods, such as technical photography, X-radiography and digital imaging. Today, every conservation or restoration is preceded by a detailed analysis of the work of art with a view to developing a suitable concept.