For the past 30 years, conservation scientists at the British Museum have been world leaders in research into the sources and effects of emissions from display and storage systems in museums. A valuable object may be housed in an enclosure such as acupboard or showcase to improve its physical security; however, this may inadvertently put an object at risk, due to emissions of harmful gases from the storage and display materials. All materials used in the storage and display of artefacts at the British Museum now have to pass one or more tests before they can be used. This has made a dramatic impact on the stability of the collection. This Occasional Paper was compiled in response to numerous enquiries received by the British Museum from a wide range of professionals: designers, architects, conservators, collectors, curators, and showcase manufacturers, and indeed anyone involved in the task of creating a safe environment for precious objects.