Although strategic position is not referred to as a business model, it incorporates many features that could be included in such a model. Porter (1991) is not specific about the contents of the components, but the model summarises his previous models and adds the causal relations between initial conditions and managerial choices and firm success. Inherent in this model is also the strategy process, as the managerial choices are seen as taking place in a longitudinal dimension and is thus a response to criticism from the process perspective field, for example Mintzberg (1978).