Scientists often try to understand the world by creating simplified or idealised models of it. And yet modelling is hard to make sense of, not least because it seems to involve learning about things that don’t exist, like ideal oscillators or perfect spheres. Models as Make-Believe offers a new approach to scientific modelling by looking to an unlikely source of inspiration: the dolls and toy trucks of children’s games of make-believe. Drawing on philosophical discussions of art and fiction, Adam Toon offers a unified framework that can solve difficult metaphysical problems posed by modelling at the same time as helping to make sense of scientific practice. In developing this new perspective, Models as Make-Believe combines careful philosophical analysis with historical and sociological approaches, shedding light on a range of issues, from scientists’ visual and tactile interaction with models to the role that cardboard cut-outs played in the development of our understanding of atoms.