This paper introduces the concept of 'object habits' for diversifying the scope of museum histories. The term is shorthand referring to an area's customs relating to objects, taking into account factors that influence the types of things chosen, motivations for collecting, modes of acquisition, temporal variations in procurement, styles of engagements with artefacts or specimens, their treatment, documentation and representation, as well as attitudes to their presentation and reception. These customs emerge not only within the museum or out in the field, but significantly between the two, within the full agency of the world. The articles in this special issue explore the potential of 'object habits' in relation to the history of museums and collections across a selection of disciplines and a range of object types, including ancient artefacts, natural history specimens, archival documents, and photographic evidence.