This masterclass aims to acquaint object and sculpture conservators with the current state of knowledge regarding identification, degradation, curative and preventive conservation of plastics, rubbers and composite materials. This four-day course is split between theoretical and practical sessions. Participants will improve their theoretical background on plastics and develop practical experience in conservation treatments such as: cleaning and adhering plastics and consolidating PUR ether flexible foams. The state of the art for preventive and active conservation will be discussed, including the latest developments in research. Participants are encouraged to bring objects or images of objects to the course for discussion.