Flexible Polyurethane (PUR) foams, in use since the 1950s and familiar from furniture upholstery and other domestic textiles, can be found in museum collections in numerous art and design objects. However, these exhibits pose severe conservation problems due to the ageing of the foam caused by photo-oxidation, leading to discoloration, loss of strength and fl exibility, and fi nally the crumbling of the object. This defi nitive work outlines the most up-to-date methods of restoring fl exibility of older foams and protecting new foams from degradation by coating them with stabilising systems acting effectively as a ‘sunblock’. The author, an experienced conservator, describes the research involved in developing the new methods and their impact on the visual, textural and chemical properties of treated PUR foams. One of the chapters details the preparation and application of the light stabilizing system to PUR foams.