When engaging with cultural heritage, we encounter questions of authenticity, ephemerality and materiality in diverse, but unavoidably intertwined ways. This volume studies these interrelations and possible approaches to associated challenges by bringing together contributions from conservation science, material culture studies and museum studies. The temporal scope of the objects discussed stretches from a rather robust existence in time and space to the fleeting moment of a performance. The material dimension of the objects stretches from the monumental buildings of industrial heritage to seemingly immaterial, time-based media artworks. As the contributions in this volume elucidate, not only are current practices of preserving the authentic diverse, but our understanding of the categories of the material, the authentic and the ephemeral is highly context-sensitive – ‘preserving the ephemeral’ is a culturally and historically dependent task. This volume sheds light on and calls for an explication of our methods and interventions in the creation, maintenance and ascription of authenticity. Key for this endeavour is close communication between different fields of research and practice in the context of cultural heritage, and the involvement of different groups of stakeholders and the public. And this collection of articles is a step in this direction.