Abstract Models of the nature of representation and cognition ground and constrain models of the construction of representation in learning and development: models of what is being constructed ground and constrain models of the processes of construction. Insofar as the notion of scaffolding is intended to refer to particular kinds of supports for learning and development, it too will be variously enabled and constrained by underlying assumptions concerning representation and cognition. I will argue that action based models of representation, which have their own powerful supports, also make possible a functional notion of scaffolding that, in turn, makes sense of processes of self-scaffolding as a central field of development.