The paper explores the central role of artworks in the field of contemporary art. It is based on an ethnographic study of the conservation laboratory at the Museum of Modern Art (MoMA) in New York and draws from three detailed case studies where the temporal and spatial trajectory of artworks led to processes of competition, collaboration, and repositioning among the agents involved in the acquisition, exhibition and conservation of these artworks. The study demonstrates the importance of artworks qua physical objects in the field of contemporary art, claiming attention to materiality in field theory and engaging with an object-oriented methodology in field analysis. Artworks are shown to intervene in field processes, both reproducing divisions and re-drawing boundaries within and between fields, and actualizing positions of individuals and institutions. © The Author(s) 2013.