In his review of Rethinking innateness (Elman, Bates, Johnson, Karmiloff-Smith, Parisi & Plunkett, 1996; henceforth, RI), Rispoli (this volume) comments favourably on the dynamical change models presented in RI's Chapter 4. I think a more critical stance is warranted. In particular, I will argue that dynamical change models cannot in principle make reference to mental representation, that the models are stipulative, and that they fail as descriptions of behaviour. (For more extensive discussion, see Valian, in press.) The relation between dynamical change models and connectionist networks is not spelled out in RI, so it is not clear which of the criticisms that I direct at dynamical change models also hold for connectionist models.