This paper reports on the experience of conservators in Leningrad (USSR) in the use of various applications of polymer compositions in restoration. Film-forming solutions or putty compress applications of carboxymethyl cellulose (CMC) and other water-soluble polymers have been used with great success in removing soiling matter from stone. Consolidation of stone with such solutions as low-viscosity polybutyl methacrylate (PBMA-LV) is reported along with introductions of new solvent mixtures and conditions of impregnation and drying. Follow-up after 25 years is reported. Special treatments for consolidation of sculpture in the open are addressed. The uses of putty based on polymer bindings and other developed compositions and techniques for reconstruction are discussed. The problems of copies and the ongoing development of polymer compositions are described. Numerous examples are given of the use of silico-organic materials in restoration.