In this chapter,1 we shall make use of a general model of Keynes–Wicksell type2 to show that these and other well-known models of cycles and growth can all be considered as special cases of this prototype model, so that they all belong to one particular theory, which despite its “Keynes–Wicksell” origin is fairly (neo)classical or supply-side oriented in nature. Such a statement does not, in our view, devalue this model type from a Keynesian perspective, but it leads us instead to a general and unifying framework of Keynes–Wicksell models3 with which models that attempt to be of a (more) Keynesian type4 can be usefully compared.