Discusses the methodlogy problems and results of the conservation of Michelangelo's frescoes on the vault of the Sistine Chapel Rome. The work started in 1980 and was completed in 1990. The decision to undertake treatment was prompted by the discovery of wide spread flaking in 1980. This flaking was provoked by layers of animal glue covering the frescoes, probably applied during concerned she colour photographic documentation of the frescoes before during treatment by Mazzuoli in the 18th century. Problems concerned and after cleaning. All aspects of the frescoes were recorded. Details of the painting technique are presented. The results of the cleaning mean that one has rediscovered Michelangelo's colour use and chromatic scheme and his technical mastery of the medium. (Details on the cleaning and cleaning agent are abstracted separately.)