Techniques of cleaning and polishing the varnish on old string instruments are discussed. Specific procedures are recommended and other common treatments are warned against. The retouching of varnish is also discussed, including the problems of matching the color of the original varnish. This article was originally presented as a paper read at the Symposium for Restorers of Non-Keyboard Musical Instruments, held at the Germanisches Nationalmuseum in Nuremberg in May 1974, and was discussed by the symposium participants: relevant material is appended to the article. See also AATA 17-1164 and 17-1195.