My primary purpose with this book is to argue that there is much to be gained from an ontological turn in social theorising, that there are significant advantages to making a concern with ontology more explicit and systematic than is the custom. A secondary goal, closely bound up with the first, and one with which I shall be expressly occupied in the current chapter, is to argue for a particular ontological conception. It is through demonstrating the sustainability as well as usefulness of this particular conception, one sometimes systematised as critical realism,1 that I seek simultaneously to achieve my primary goal.