This article is a contribution to the clarification of the central claim of Kenneth Waltz’s neorealist international relations theory. Over the years, the notion that Waltz’s Theory of International Politics postulates a deterministic connection between the configuration of the structure of the international system and the behaviour of each of the units has gained traction in textbooks and in straw-man critiques of the neorealist approach. Two major groups of critics of neorealism’s alleged determinism have formed. The first group focuses on instances where predicted balancing behaviour did not occur in order to refute neorealism’s central claim about the link between structure and behaviour. The second group objects to any strong claims about structural features as such. In response, this article shows that a careful reading of Waltz’s writings suffices to indicate that the presupposition adopted by both groups of critics is flawed. Neorealism was never presented by its main proponent as a deterministic international relations theory.